CACHE MEMORY

CACHE MEMORY

When the processer needs to study from or create to a place in primary storage, it first assessments whether a copy of that information is in the storage cache. If so, the processer instantly flows from or creates to the storage cache, which is much faster than reading from or writing to primary storage.
Most modern pc and hosting server CPUs have at least three separate caches: an training storage cache to rate up exe training bring, a information storage cache to rate up information bring and store, and a interpretation lookaside barrier (TLB) used to rate up virtual-to-physical deal with interpretation for both exe guidelines and information. The information storage cache is usually structured as a structure of more storage cache levels (L1, L2, etc.; see Multi-level caches).
Data is moved between storage and storage cache in prevents of set size, known as storage cache collections. When a storage cache range is duplicated from storage into the storage cache, a storage cache access is created. The storage cache access will include the duplicated information as well as the asked for storage place (now known as a tag).
When the processer needs to study or create a place in primary storage, it first assessments for a corresponding access in the storage cache. The storage cache assessments for the material of the asked for storage place in any storage cache collections that might contain that deal with. If the processer discovers that the storage place is in the storage cache, a storage cache hit has happened (otherwise, a storage cache miss). In the case of:
a storage cache hit, the processer instantly flows or creates the information in the storage cache range.
a storage cache skip, the storage cache allocates a new access, and duplicates in information from primary storage. Then, the demand is satisfied from the material of the storage cache.
The proportion of accesses that result in a storage cache hit is known as the hit rate, and can be a measure of the potency of the storage cache for a given program or criteria.
Read overlooks delay performance because they require information to be moved from storage much more slowly than the storage cache itself. Write overlooks may occur without such charge, since the processer can continue performance while information is duplicated to primary storage in the background.
Instruction caches are similar to information caches, but the CPU only functions study accesses (instruction fetches) to the training storage cache. (With Stanford structure and customized Stanford structure CPUs, training and information caches can be divided for higher performance, but they can also be mixed to reduce the components expense.)

TYPES OF HACKER

TYPES OF HACKER-WHITE HAT AND BLACK HAT


A white hat cyberpunk forces security for several reasons, probably to evaluate their own security software or while working for a security company which makes protection software. The phrase "white hat" in Internet language shows an ethical cyberpunk. This group also has individuals who execute transmission assessments and weeknesses tests within a contract contract.
A "black hat" cyberpunk is a cyberpunk who breaks pc protection for little reason beyond maliciousness or for personal gain. Black hat online hackers type the clichéd, illegal hacking categories often showed in well-known way of life, and are "the perfect example of all that the community worries in a pc criminal". Dark hat online hackers crack into secured systems to eliminate information or make the program useless for those who are accepted to use the program. They select their goals using a  method known as the "pre-hacking stage".
The cyberpunk selects what application to crack into during this stage. The focus on may be of special attention to the cyberpunk, possibly  mixed or  individually, or it may be selected at distinctive. Next, they will slot check out a program to figure out if it is sensitive to strikes, which is just analyzing all slots on a wide range system for a reaction. Start ports—those that do respond—will allow a cyberpunk to availability the program.
Part 2: Research and Details Gathering
It is in this stage that the cyberpunk will check out or contact the focus on in some way in needs of working out important information that will help them accessibility the program. The main way that online hackers get preferred results from this level is from "social engineering", which will be described below. Aside from community technological innovation, online hackers can also use a strategy . Reject snorkeling is when a cyberpunk will basically search through users' .Desires of discovering information that have been tossed away, which may contain information a cyberpunk can use straight or eventually, to help them get entry to a program.
This is the level when the cyberpunk will get into the main focus on that he/she was planning to strike or pick up from. Many "online hackers" will be captured after this point, attracted in or got by any details also known as a honeypot.

HACKER

HACKER-INTRODUCTION AND CLASSIFICATION


In the pc protection point of view, a nuller is somebody who looks for and uses mistakes in a software or pc system. Online  hackers may be inspired by lots of reasons, such as benefit, display, or task. The sub-culture that has developed around online hackers is often termed as the pc undercover and is now a known team. While other uses of the phrase nuller are available that are not appropriate to pc security, such as referring to someone with a high level knowing of pcs and pc programs, they are hardly ever used in well-known viewpoint.[citation needed] They are topic to the conventional nuller meaning discussion about the real significance of the word nuller. In this discussion, the word nuller is gotten back by designers who declare that someone breaking into pcs is better known as a celebration party cracker, not making a distinction between pc fraudsters (black hats) and pc security experts (white hats). Some white-colored hat online hackers announce that they also are eligible to the headline nuller, and that only black hats should be identified as cookies.
Many subgroups of the pc undercover with various methods use numerous situations to demarcate themselves from each other, or try to remove some particular team with which they do not consider the fact. Eric S. Raymond (author of The New Hacker's Dictionary) supporters that associates of the pc undercover should be known as biscuits. Yet, those people see themselves as online hackers and even try to consist of the opinions of Raymond in what they see as one wider cyberpunk lifestyle, a viewpoint severely denied by Raymond himself. Instead of a hacker/cracker dichotomy, they give more focus to a variety of different groups, such as white-colored hat, dull hat, black hat and program kids. Contrary to Raymond, they usually source the phrase special event cracker for more harmful action. According to (Clifford R.D. 2006) a celebration cracker or splitting is to "gain illegal entry to a pc in order to make another lawbreaker action such as ruining information included in that system". These subgroups may also be defined by the legal place of their actions

ANTIVIURS

IMPORTANT ABOUT ANTIVIURS

13th Feb 2013 A program is designed to secure all factors of your electronic life. Intego has entirely reworked its items with an user-friendly, structured consumer experience that needs almost no settings out of the box, provides valuable reports and signals, and is a perfect complement to the Mac OS X base. Intego's anti-virus and Mac security items are traded on its web page in many, providing padded security that takes the anxiety out of defending your electronic resources and identification details.

The Mac Online Protection Top quality 2013 program provides jointly three of Intego's top-selling items to secure you and your data against viruses, program strikes, and the loss or robbery of your Mac. It is the ideal mixture of protection and satisfaction.

The Intego Mac Online Basic safety Top quality 2013 bundle contains:

Virus Hurdle 2013: Battles Mac and Microsoft windows viruses that endanger your security.
Net Hurdle 2013: Maintains unidentified people and dubious programs out of your Mac.
Identity Scrubber: New to Intego's Mac security item promotions, Identity Scrubber queries for delicate identification details saved on your pc and defends or erases it at your control (available in the British terminology edition of Intego Mac Online Security Top quality 2013).
Intego's 2013 protection items offer an stylish and clean user software that gives you straightforward, at-a-glance views of what your Mac is doing and any risks you may encounter. After the advised set-up process, your Mac will immediately prevent unnecessary system traffic and check out for viruses in the history, making it easy to stay safe as you move between your house system, a restaurant hot spot, or perform. Intego has also removed little-used features and choices choices that included complexness to past years of items. The outcome is a much more user-friendly, "Mac-like" encounter.

"With the growing popularity of the Mac, online online hackers and cyber-criminals are seeing a bigger industry to manipulate for harmful specifications. Yet 75 percent of Mac clients still don't use devoted security application to secure their Mac pcs, and house and public Wi-Fi systems also stay primarily unprotected," said Mark Erwin, CEO of Intego. "As the only security company targeted specifically on the Mac sector and die-hard Mac customers ourselves, we have a unique knowing of the way Mac customers predict application to carry out. We've provided a package of items that shows the convenience and design visual of the Mac experience but still provides extensive security.

For specific item explanations, and to buy Intego's new 2013 Mac protection application.
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Mac OS X 10.6 or higher
Mac pc with Apple Primary 2 Duo processor
1.5 GB of accessible challenging drive space
Internet connection for NetUpdate security updates
 Costs and Availability:

For pricing details, please visit Intego's website

MALWARE -INTRODUCTION

MALWARE -INTRODUCTION

Malware is a  dangerous  application, is software used or produced by assailants to affect pc function, collect delicate details, or get entry to private pcs. It can appear by means of code, programs, effective content, and other application. 'Malware' is a popular term used to refer to a variety of forms of aggressive or invasive application.
Malware includes pc malware, ransomware, viruses, trojan viruses horse, rootkits, remote monitoring software, dialers, malware, malware, harmful BHOs, fake protection application, and other harmful programs; almost all efficient malware risks are usually viruses or trojan viruses viruses rather than viruses. In law, malware is sometimes known as a pc toxic, as in the legal codes of several U.S. states.Malware is not the same as faulty software, which is software that has a genuine purpose but contains harmful bugs that were not fixed before release. However, some malware is hidden as genuine application, and might come from an established company website. An example of this is application used for safe purposes that is packed with additional following application that accumulates promotion study.
Malware has caused the development of use of protective application kinds such as antivirus, anti-malware, and fire walls. Each of these are commonly used by individual customers and business networks in order to stop the illegal accessibility by other people who use computer systems, as well as the computerized propagate of dangerous programs and application.
Many early infected applications, including the first Online Worms, were written as tests or practical jokes. Today, malware is used primarily to grab delicate individual, financial, or business details for the benefit of others.
Malware is in some cases used generally against administration or organization websites to collect covered details, or to affect their function in common. However, malware is often used against individuals to obtain individual details such as social safety figures, bank or bank card figures, and so on. Left un-guarded, individual and networked laptop or computer systems can be at considerable risk against these risks. (These are most regularly counter-acted by various kinds of fire walls, antivirus application, and network hardware).
Since the increase of extensive broadband Online network, harmful application has more consistently been developed for benefit. Since 2003, almost all extensive viruses and viruses have been developed to take control of users' computer systems for black-market exploitation.Polluted "zombie computers" are used to send email junk, to host contraband data such as child porn, or to engage in distributed denial-of-service attacks as a way of extortion.
Another totally for-profit category of spyware has appeared, called viruses. These software are formulated to monitor users' web browsing, screen excess ads, or divert internet marketing earnings to the malware creator. Spyware and adware applications do not propagate like viruses; instead they are generally set up by taking advantage of protection gaps. They can also be packed together with user-installed application, such as peer-to-peer applications

ANTIVIRUS

AN INTRODUCTION TO ANTIVIURS


Anti-virus or anti-virus system is application used to prevent, identify and eliminate malware (of all descriptions), such as: laptop or computer malware, harmful BHOs, hijackers, ransomware, rootkits, trojan viruses horse, viruses, destructive LSPs, dialers, malware. Computer protection, such as protection from social technological innovation methods, is commonly provided in products and professional services of anti-virus application businesses. This page talks about the application used for the avoidance and reduction of malware risks, rather than system protection applied by application methods.
A selection of methods are typically employed. Signature-based identification contains looking for known styles of data within exe value. However, it is possible for a laptop or system to be contaminated with new malware for which no unique is yet known. To reverse such so-called zero-day risks, heuristics can be used. One type of heuristic strategy, common signatures, can identify new malware or versions of present malware by looking for known harmful value, or minor modifications of such value, in data files. Some anti-virus system can also estimate what a file will do by running it in a sand pit and evaluating what it does to see if it functions any harmful activities.

No issue how useful anti-virus application can be, it can sometimes have disadvantages. Antivirus application can damage a pc's performance. Beginner users may also have complications understanding the encourages and choices that anti-virus application provides them with. An wrong decision may lead to a protection violation. If the anti-virus application utilizes heuristic identification, success relies on accomplishing the right balance between wrong advantages and wrong disadvantages. False advantages can be as dangerous as wrong disadvantages.[1] Lastly, anti-virus application generally operates at the highly reliable kernel level of the os, creating a potential opportunity of attack.

INTERESTING NEWS ABOUT LINGUISTICS

INTERESTING NEWS ABOUT LINGUISTICS

The linguistics technologies behind contemporary search engines is fairly primary. Let me describe what I mean here. Look for search engines are currently included with precise methodology: they provide fast results but without any terminology analysis; they evaluate huge amounts of written text information on the system and the record of concerns that have been fed in.
It’s a way of implementing a current statistical strategy to machine-learning, but the search requirements keep no regards to any analysis of significance.
We’ve got a unique way of working. We want to evaluate the semantic vicinity of the query to the writing it discovers, based on semantic analysis. Sure — it’s more dangerous and it costs more, so less people go down this “knowledge-hungry” path. The search engines and Ms Research have been doing relevant analysis on this things.
Actually, fundamentality was our significant issue when we went forward with the technique we’re using. From the beginning we took the fairly expensive and resource-intensive decision to develop a global terminology design that forced us to follow a specific series. When you work  for a terminology, you cannot keep out any of the stages: you need a complete morphology, format, semantics, lexical semantics, and so on.
Creating the terminology design required us a when, and you can add the information of any vocabulary to it. What we designed was a design that validated its own performance, and we reviewed it in five 'languages' — European, British, In german, France and China.

VIRTUAL PRIVATE NETWORK

VIRTUAL PRIVATE NETWORK

A exclusiveindividual program (VPN) improves a particular person program and the resources in the program across group techniques like the On the internet. It allows a wide variety computer to provide and get data across allocated or group techniques as if it were a individual program with all the performance, safety and management referrals of the person program.[1] This is done by creating a unique point-to-point connection through the use of dedicated connections, protection, or an wide variety of the two.
The VPN connection over the On the internet is formally a comprehensive area program (WAN) weblink between the websites but seems to the consumer as a individual program link—hence the name "virtual individual network".

Beginning details techniques allowed VPN-style far away partnership through dial-up places or through leased variety connections using Structure Connect and Asynchronous Return Technique (ATM) unique trip provisioned through a program handled by telecom suppliers such as AT&T or Verizon. These strategies are not considered actual VPNs because they passively secured the details being approved on by the growth of sensible details resources.[3] They have given way to VPNs based on IP and IP/Multiprotocol Product Modifying Programs (MPLS) structured VPNs due to essential cost-reductions and enhanced bandwidth offered by new technological innovation such as Digital Consumer Range (DSL) and fiber-optic approaches.
VPNs can be either remote-access (connecting an individual pc to a network) or site-to-site (connecting two techniques together). In a organization developing, remote-access VPNs allow employees to availability their company's intranet from home or while traveling to outside the office, and site-to-site VPNs permit employees in geographically separated work environments to talk about one organic unique program. A VPN can also be used to interconnect two similar techniques over a different middle network; for example, two IPv6 techniques over an IPv4 program.
VPN techniques can be identified by:
the techniques used to tunel the traffic
the tunnel's cancellations factor, i.e., client benefits or network-provider edge
whether they provide site-to-site or remote-access connectivity
the levels of security provided
the OSI part they current to the connecting program, such as Part 2 trip or Part 3 program connectivity

NEWS FOR DISABLED PERSON

NEWS FOR DISABLED TO USE COMPUTERS

When his back did not support him , Larry Rodriguez felt like he was mostly alone in the world.

One day,he had fallen asleep behind the wheel of his truck coming home from work late one night, and the 1992 accident left him paralyzed below his waist.

When he  healed  after the crash to get used to life in a wheelchair, Rodriguez joined  his job at Los Alamos National Laboratory. But he could not perform his job as well as before, so he worried. He tried to find work that he could perform from his rural home near Española.

I was not doing anything. I was just feeling sorry for myself, he said. A lot of that time, I considered myself the Lone Ranger. I’m out here in the boonies in a wheelchair alone.

Ten years later, Rodriguez still had not found another job. He was passed over for many opportunities, he said, because of his physical disability and because people made assumptions about his mental competency.

Rodriguez is one of hundreds of New Mexicans who are on the job now, thanks to a little-known law called the State Use Act. The rules direct state contracts to companies owned by those with disabilities and programs that hire people with disabilities. Rodriguez, 55, is now putting his computer-science degree to use as a technician at the Adelante Development Center in Albuquerque. He refurbishes computers for state agencies, including the state Department of Health.

Moving to Rio Rancho and re-entering the workforce in 2010, he said, made a huge difference in his general outlook.

“I talk to people. I’m going out and about. I don’t just sit around,” he said. “I’m using my head, solving problems with these computers.”

Rodriguez is among about 351 people who were employed through State Use contracts last year. Not everyone who’s tried to tap into the contracting plan has met success, however.

Susan, a Santa Fean who didn’t want her last name published, said she’s been signed up as a qualified member with the nonprofit program’s administrators since 2009 but has not found any work, even though she has a doctoral degree and a number of marketable skills, such as writing, editing and teaching. While the first nonprofit that administered the State Use Act, NM Abilities, communicated with her regularly about potential contracts, she said communication from the program’s current administrator, Horizons of New Mexico, has been nonexistent.

“While 351 jobs are more than nothing, I wonder if they amount to a whole drop of anything in anyone’s concept of a statewide bucket,” she said. “Sharing the information about what ‘scope of work’ is available just might allow for more participants to receive contracts with the state.

“Meanwhile, an entire segment of the workforce stands underused, discarded, excluded and waiting to contribute to and strengthen our interconnected, interdependent framework of society.”

DIGITAL CAMERA

INTRODUCTION TO DIGITAL CAMERA
WORKING AND RESOLUTION

A digital camera (or digicam) is a camera that takes video or still photographs by the process of recording  images on an electronic image sensor. Most cameras sold today are digital and digital cameras are incorporated into many devices ranging from PDAs and mobile phones (called camera phones) to vehicles.
Digital and film cameras share an optical system, typically using a lens with a variable diaphragm to focus light onto an image pickup device. The diaphragm and shutter admit the correct amount of light to the imager, just as with film but the image pickup device is electronic rather than chemical. These cameras, digital cameras can display images on a screen immediately after being recorded, and store and delete images from memory. These cameras can also record moving video with sound. Some digital cameras can crop and stitch pictures and perform other elementary image editing.
The resolution of a digital camera is often limited by the image sensor   that turns light into discrete signals. The sensor is made up of millions of "buckets" that essentially count the number of photons that strike the sensor. The brighter the image at a given point on the sensor, the larger the value that is read for that pixel. Depending on the physical structure of the sensor, a color filter array may be used which requires a demosaicing/interpolation algorithm. The number of resulting pixels in the image determines its "pixel count". For example, a 640x480 image would have 307,200 pixels, or approximately 307 kilopixels; a 3872x2592 image would have 10,036,224 pixels, or approximately 10 megapixels.

Since the first digital backs were introduced, there have been three main methods of capturing the image, each based on the hardware configuration of the sensor and color filters.

The first method is often called single-shot, in reference to the number of times the camera's sensor is exposed to the light passing through the camera lens. Single-shot capture systems use either one CCD with a Bayer filter mosaic, or three separate image sensors 

The second method is referred to as multi-shot because the sensor is exposed to the image in a sequence of three or more openings of the lens aperture. There are several methods of application of the multi-shot technique. The most common originally was to USE single image sensor with three filters (once again red, green and blue) passed in front of the sensor in sequence to obtain the additive color information. Another multiple shot method is called Microscanning. This technique  moved the physical location of the sensor chip on the focus plane of the lens to "stitch" together a higher resolution image than the CCD would allow otherwise. A third version combined the two methods without a Bayer filter on the chip.

Dramatic improvements in single-shot cameras and raw image file processing at the beginning of the 21st century made single shot, CCD-based cameras almost completely dominant, even in high-end commercial photography. Single shot cameras remained somewhat common.

WINDOWS OPERATING SYSTEM

WINDOWS OPERATING SYSTEM
Windows operating system is a family of operating system for personal computers .It is the most popular operating system used on personal computers .Almost 90%  personal computers in the world use Windows.It was developed by MICROSOFT CORPORATION.
Windows provides graphical user interfance (GUI) .It uses windows,icons,menus and other graphical objects to issue commands .It supports many peripheral devices such as mouse and keyboard .Mouse is the most commonly used input device in this operating system.

HARD DRIVE
A Hard Drive is the main storage media.The hard drive is typically designated C:\ drive .A hard drive can be divided into logical parts . Each partition is also assigned a drive letter.If the hard drive is divided in four partitions ,these partitions are called c:.d:.and E: drive

FLOPPY DRIVE
It is used to read/write  smaller volumes of data on floppy disk.It is typically designated  A:\.The common size of floppy drive is 3.5" and its capacity is 1.44 MB

CD-ROM DRIVE
It is used to read data from CD-ROM .These drives are typically labeled after the hard disk drive.

DATA ORGANIZATION IN DOS

DATA ORGANIZATION IN DOS
DOS divides the secondary storage of computer into logical areas knowns as drives.Each drive is recognized by a letter followed by colon.For example ,the first floppy drive is called A: drive and second floppy drive is called B: drive. The hard disk may be assigned the letter c and called c: drive and CD drive may be called D: drive.
The capacity of hard is commonly very large.It is normally divided int logical parts called partitions.The FDISK utility is used to divide the hard disk into partitions .Each partition is aslo assigned a drive letter.If the hard disk is divided in four partitions ,these partitions  are called C:,D:,E: etc
The data on drives is organized in the form of directories and files.A logical division of a drive where files are stored is known as directory.A drive may have many directories .DOS creates a directory on the disk automaticlly when the disk is formatted .This directory is called root directory.A directory within a directory is called subdirectory.
The directory in which the user is currently working is called as present working directory.
DOS interprets all commands with reference to the present working directory until the user specifies any other directory.

plotter

PLOTTER
It is a large scale printer.It recieves commands from computer to make drawings on  paper. It creates an output using one or more automatic pens.A plotter can draw continuous point to point lines from computer graphics files.They are much expensive than printers.They are frequently used for computer aided engineering


TYPES OF PLOTTER
DRUM PLOTTER

                              It is a plotter that creates output by using a pen or drumThe paper is wrapped on the drum that roatates back & forth                                    

PRINTER-INKJET

PRINTER-INKJET
An Inkjet Printer is a type of non-impact printer.It prints characters and graphics by spraying tingy drops of liquid ink on paper.These printers can produce quality text and graphics in both black and white and color including photos.A typical injet printer provides resolution of 300 dots per inch or more.The latest inkject printer provide higher resolution
The price of Inkjet printer is less than laser printer.However,they are slower than laser pinter
Print quality of inkjet printer is better than dot matrix printer/They are comparativly inexpesive.
Most of Inkjet printer are frequenty used in the wolrd
ELECTROSTATIC PRINTER
An electrostatic printer is a type of non impact princter It uses a special paper for printing.It creates characters on paper by using stylus.It places an electrostaic charged image on the paper to create character.The paper is moved through a solution that contains ink particles.The ink adhere to the chatges that create a paterns on paper to develop the image

DAISY WHEEL PRINTER

DAISY WHEEL PRINTER
It is similar to a typewriter.It uses a print wheel.print wheel is called daisy wheel.Each petal of daisy wheel contains characters.A motor rotates the wheel.A hammer strikes a petal agaisnt the ribbon when the desired character reaches the position on the paper.This print the character on the paper.It is slower than dot matrix printer but better in quality.
It cannot print graphics.It cannot change the fonts unless the print wheel is physically replaced.These printers are not used in modern computing.
LINE PRINTER
It is a fast impact printer.It can print multiple character on the same line at a time.Its speed is measured in LPM(Lines per minute) These are faster than daisy wheel and dotmatrix printer
They produce lower quality printing.It uses special paper that has holes in themIt helps to print at very high speed.This arrangement helps to helps to continue helps the printer till paper ran out
EXMPLRD PRINTER
                                     
                

OUTPUT DEVICE

OUTPUT DEVICE-MONITOR
The monitor is the most commonly used output device.It is asl known as display or screen.The user looks at moniotr while performing different tasks such as typing,issuing commands or srfing the Internet .The quality of the image displayed on screen depends on many factors
An important factor that affects the quality of moniotr is called resolution.Resolution is the number of pixels on the screen .It is expressed as a matrix.All moniotrs can be categorized by the way they display colors

Different categories are  as follows

Monochorome : This monitor can dispaly only one color such as green ,amber or white.It usually uses black color as background.It can display only text.It is not  used to display graphics


Color Monitor:This monitor displays the combinations of red,green and blue colors.These are basic colors.A combination of these colors can display full range of colors.

INPUT DEVICES

INPUT DEVICE-LIGHT PEN
Light Pen is a light sensitive input device.Its shape is similar to a traditional  pen.It is used to draw on compute screen or select menues.It is connected by a wire to a computer.It has a device at its tip that emits light.The pen sends information to the computer when user touches the pen on certain areas of a specially designed screen.The information contains the x-y coordinates of the position of pen
Light Pen provides all features of mouse.The user can interact more with applications by using options such as drag and drop .It also provides more active and accurate interaction between user and computer system.Light pen is usually used by engineers and graphic designers.
It is now using by lot of users of computer who feels it much better .
INPUT DEVICE-DIGITAL CAMERA
Digital Camera is an input device.It stores images digitally in its memory rather than recording on film.The pictures taken with a dighital camera can be downloaded on computer system.The pictures can be processed further with graphics programs.The digital photos are limited by the amount of memory in the camera.The main advantage of digtial camera is that making photos is inexpensive and fast.It doesnot require any film processing

PARALLEL AND USB PORTS

PARALLEL AND USB PORTS
A type of port that transmits many bits at a time is called parallel port.It is much faster than a serial port.It is usually used to connect devices that require fast data transmission like printer and scanner.Parallel ports are often referred to as Line Printer (LPT )Port.The largest port on the back of the computer consists of 25 pins

USB PORT
It stands for Universal Serial Bus .It is a plug and play hardware interface.It is used to connect devices such as keyboard ,mouse ,joystick ,scanner and printer .It has a maximum bandwidth of 12 Mbps.It can connect 127 devices .The new device can be added without adding and adapter card.It is typically located on the back of the computer.Some computers provide USB port on the front side of system unit.

PORTS OF COMPUTER

PORTS OF COMPUTER
A Port is an interface or point of attachment .It is used to connect peripheral devices with computer such as printers ,keyboards or mouse.All Peripheral devices communicate with the computer using ports.The port connectors are attached to motherboard .Each type of port operates at a certain speed.The speed is measured in kbps.
TYPES OF PORTS
Different types of ports are as follows

       Serial Port
       Parallel Port
        USB Port
SERIAL PORT
A type of port that transmits one bit at a time is called serial port.It is usually used to connect devices that donot require fast data transmission like mouse and keyboard etc.Serial port is often referred to as Communication (COM) Port.It is an external port on the back of the computer.It is attached directly to motherboard.The older ports used 25 pin connectors for serial port.The serial ports in the latest computers have only nine pins.

INTRODUCTION TO DATA BUS AND ADDRESS BUS

INTRODUCTION TO DATA BUS AND ADDRESS BUS

Data bus is the most  common bus .It is used to carry data .It is an electrial paht that connects CPU,memory ,input/output  devices and seconday storage devices.The bus contains parallel set of lines.The number of lines affects the speed of data transfer between different components .A data bus with more lines can carry more data.A data bus with 16 lines can carrry 16 bits (2 bytes) of data. A data bus with 32 lines can carry 32 bits (4 bytes) of data.A bus is designed in such way that it can communicate with components efficiently .The buses in old computers could carry only one byte of data.The buses used today can carry multiple bytes at one time.It improves the speed and perfomarnce of computer system

Address bus is used to carry address information.It is a set of wires similar to data bus.It only connects central processing unit and memory.

    The following steps take place when CPU needs data from the memory

          CPU places the address of required data on address bus

           The address bus is carried to the memory

            The data from the requested address is fetched and placed on data bus

            The data bus carries the data to CPU

The number of lines in the address bus detemines the maximum bumber of memory addresses.If an address bus has 8 lines ,the maximum number of memory locations that can be addressed are 256 .The computers used today have 32 bit address lines .These computers can access 4GB of memory.

INTRODUCTION TO SYSTEM BUS

INTRODUCTION TO SYSTEM BUS

A Computer system consists of different  devices.CPU must be able to communicate with all devices.The devices are connected together by a communcation channel called bus.A bus consists of a set of communication lines or wires .It is used to move a large amount of bits in the form of electrical pulses from one unit to another

The bus is used to connect the following units

  Central Processing Unit

             Control Unit

              Arithmetic and Logic Unit

   Main Memory(RAM,ROM)

   Input /Output Devices

---------------------------

Bus is a Common path to transfer data and commands between CPU ,memory and input/output devices

It is also used to send or recieve data from secondary storage devices.The Capacity of a bus depends on the number of lines in it.A bus with 16 lines can carry 16 bits or 2 bytes at a time.A bus with 32 lines can carry 32 bits or 4 bytes at a time.system buses are part of motherboard

Different types of system buses are as follows

        Data bus

       Address bus

        Control bus

APPLICATION OF COMPUTERS IN BUSINESS

APPLICATION OF COMPUTERS IN BUSINESS
================================

Computer is used widely in Business and industry .Many business tasks are performed more quickly and efficiently using computers .Computers information systems are used to store the record of huge transactions .The transactions can be made from anywhere in the world with the help of computer and internet.Computer is widely used in buniness community to reduce the administrative paperwork .It also reduces the cost.

Computers can be used to business for the following purposes
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1.Controlling the machines in the process of product manufacturing
2.Keeping track of customers's bills
3.Analyzing sales of various products in different locations
4.Analyzing sales of various products on monthly and yearly basis
5.Calculating and recording employee pays

APPLICATION OF COMUTERS IN EDUCATION

APPLICATION OF COMUTERS IN EDUCATION
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Computer is playing very important role in educaion field .The educational institutes of primary to university level are using computers for various avtivities .A large no of learning programs are available on every subject.These tutorials provide one- to - one interaction with the student.The trend of online examinations are  becoming popular
Different examinations like GRE,GMAT and SAT  are conducted  online all over the world.The questions are marked by computer.It minimizes the chance of mistakes .It also enable to announce the result in time
DISTANCE Learning  is a new learning methodology .Computer plays the key role in the kind of learning .Many institutes are providing distance leaning programs.The Student doesnot need to come to institute .The Institue provides the reading material and student attends the virtual class rooms .In virtual class rooms ,the teacher delivers lecture at his own workplace.The student can attend the lecture at home by connecting to a network .The student can also ask questions to the teacher.The answers are given to the students by email
Computer also helps students to find every thing search on every topic and then discuss his fellows and this makes the ability of students more and more strong.

LANGUAGE TRANSLATOR

LANGUAGE TRANSLATOR
It is a program that translates a program of high level language or assembly language into machine code.Every computer language has its own translator .Computer understands only machine language.A program written in high level or assembly language cannot be run on a computer directly .It must be converted into machine language before execution
Different types of Language translators are as follows
COMPILER
INTERPRETER
ASSEMBLER
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COMPILER
                    It is a program that converts the instructions of a high level language into machine language as a whole.A program written in high level language is called source program.The Compiler converts the source program into object program.The compiler checks each statement in the source program and generates  machine instructions .Compiler also checks syntax error in program .A source program having error cannot be compiled.A compiler can translate the programs of only  those languages for which it is written .For example ,Compiler can translate only those programs that are written in C language
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INTERPRETIER
                            An Interpreter is a program that converts one statment of program into machine at one time.It executes a statement before translating the next statement of source program.If there is an error in the statements ,interpreter stops working and displays an error message
The advantage of interpreter over compiler is that an error is found immediately so the programmer can correct errors during program development.The Interpreter does not produce an object program
It must convert the program each time it is executed
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Assembler
                An assembler is a translating program that translates the instructions of assembly language into machine language

POSITIVE IMPACT OF COMPUTERS

POSITIVE IMPACT OF COMPUTERS
Computer has made a very vital impact on our society.It has changed the way of life.The Use of computer technology has affected every field of life.People are using computers for perfoming different tasks quickly and easily .The use of computers makes different tasks easier.It also saves a lot of time and effort.It also reduces the overall cost to complete a particular taks
Many Organinzations are using computer for keeping the records of their customers.Banks are using computers for maintaining accounts and managing financial transactions .
The transactions are handled easily and quickly with computerized systems.People are usning computers for paying their bills.
They are getting information from the internet.They also use computers to manage their home budget
Computers can be used in education field to improve from the internet .They also help to update the studies effectively
Moreover,the computer is being used in every field of life such as medical,business,airline and weather forecasting

disk drive

DISK DRIVES
Disk Drive is used to read and write data on a disk.It has one or more read/write heads to read and write data.There are different types of disk drives for different types of disk.For example a floppy drive reads and writes data from floppy disk

SRAM AND DRAM

DIFFERENTIATE BETWEEN SRAM AND DRAM
DRAM holds its data dynamically .It doesnot hold it indefinitely.Each DRAM memory cell must be constantly refreshed to keep data in DRAM.
SRAM doesnot require refreshing .It holds the data indefinitely as long as computer remains on.

It is faster than DRAM but it is very complex 

memory

DIFFERENTIATE BETWEEN PRIMARY AND SECONDARY MEMORY
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Primary memory is expensive and small but secondary memory is inexpensive and large.Primary memory directly connects to CPU but Secondary mimory is not directly connected to CPU.
Primary memory provides faster data access but secondary memory provides slow data access

MULTIMEDIA

MULTIMEDIA
It is a combination of text ,audio,animations ,still images.It is run by information content precessing devices
such as computerized devices,It can also a part of live process.It has a broader scope than max media
It can be linear and non linear

Linear without naviagation control  such as cinema screen
Linear with control---------------  such as video game

Disadvnatages of BroadBand

DISADVANTAGES OF BROADBAND

Highly monthly charges

It can not support in rural and some distant areas

It can not work where PTCL facility is not available

Due to lack of firewall ,security risk is there for protection of computer

Advantages of BroadBand

ADVANTAGES OF BROADBAND
Following are main advantages of using BroadBand
1.Connection Speed Up to 100 times faster
2.It doesnot affect the phone line
3.This connection is always on
4.No special cable is required

MOBILE WIRELESS BROADBAND

MOBILE WIRELESS BROADBAND

Wireless broadband technology include service from mobile phone service such as AT &T Mobility 

This type of connection cna be stable in almost any area that could also receive a strong cell phone connection

The Iphone service in USA experienced the problem of heavy internet use more than any other providers

Smart Phone Customers use 40 % of the technology use

Iphone is a great achievment in the world of networking for proper and correct funcioning of network traffi

BROADBAND-WELCOMEIT

BROADBAND-INTRODUCTION
It refers to the bandwith of a transmission medium and its ability to transport multiple signals and traffic types at the same time.Medium can be in any kind of form e.g coaxial cable,optical fiber and twisted pair .
A baseband is a system in which information is transported across a single channel
Diap up Internet was the only way  by which one can access the internet and download files such as movies and songs
The cable modem is common use of broadband .If we have a broad band connection then we can download any thing much faster than dial up modem

Different criteria for "broad" have been applied in different contexts and at different times. Its origin is in physics, acoustics and radio systems engineering, where it had been used with a meaning similar to wideband. However, the term became popularized through the 1990s as a vague marketing term for Internet access.

WI-FI

WI-FI
WIRELESS FIDELITY

Wi-Fi  also spelled Wifi or WiFi) is a popular technology that allows an electronic device to exchange data wirelessly (using radio waves) over a computer network, including high-speed Internet connections. The Wi-Fi Alliance defines Wi-Fi as any "wireless local area network (WLAN) products that are based on the Institute of Electrical and Electronics Engineers' (IEEE) 802.11 standards" However, since most modern WLANs are based on these standards, the term "Wi-Fi" is used in general English as a synonym for "WLAN". Only Wi-Fi products that complete Wi-Fi Alliance interoperability certification testing successfully may use the "Wi-Fi CERTIFIED" trademark.

A device that can use WI-Fi  that can connect to a network resource such as the internet using wirless network access point such an access point has range of about 20 meters indoors and greater range outdoors

Hotspots range can comprise as area as  small as a single room with wallls that block radio waves

A device that can use Wi-Fi (such as a personal computer, video-game console,smartphone, tablet, or digital audio player) can connect to a network resource such as the Internet via a wireless network access point. Such an access point (or hotspot) has a range of about 20 meters (65 feet) indoors and a greater range outdoors. Hotspot coverage can comprise an area as small as a single room with walls that block radio waves or as large as many square miles — this is achieved by using multiple overlapping access points.

It can be less secure than wired connections because an intruder doesnot need a physical connectio ,web pages that use ssl are seure