Common network terms

Node

In communication networks, a node (Latin nodus, ‘knot’) is a connection point, either a redistribution point or a communication endpoint (some terminal equipment). The definition of a node depends on the network and protocol layer referred to. A physical network node is anactive electronic device that is attached to a network, and is capable of sending, receiving, or forwarding information over a communications channel.A passive distribution point such as a distribution frame is consequently not a node.In network theory or graph theory, the term node refers to a point in a network topology at which lines intersect or branchIn data communication, a physical network node may either be a data circuit-terminating equipment (DCE) such as a modem, hub, bridge or switch; or a data terminal equipment (DTE) such as a digital telephone handset, a printer or a host computer, for example a router, a workstation or a server.If the network in question is a LAN or WAN, every LAN or WAN node (that are at least data link layer devices) must have a MAC address. Examples are computers, packet switches and ADSL modem (with Ethernet interface). Note that a hub constitutes a physical network node, but not a LAN node in this sense, since a hubbed network logically is a bus network. Analogusly, a repeater or PSTN modem (with serial interface) are physical network nodes but not LAN nodes in this sense.If the network in question is the Internet, many physical network nodes are host computers, also known as Internet nodes, identified by an IP address, and all hosts are physical network nodes. However, datalink layer devices such as switches, bridges and WLAN access points do not have an IP host address (except sometimes for administrative purposes), and are not considered as Internet nodes, but as physical network nodes or LAN nodes.If the network in question is a distributed system, the nodes are clients, servers or peers. In a peer-to-peer or overlay network, nodes that actively route data for the other networked devices as well as themselves are called supernodesIn the fixed telephone network, a node may be a public or private telephone exchange, a remote concentrator or a computer providing some intelligent network service. In cellular communication, switching points and databases such as the Base station controller, Home Location Register, Gateway GPRS Support Node (GGSN) and Serving GPRS Support Node (SGSN) are examples of nodes. Cellular network base stations are not considered as nodes in this context.In cable television systems (CATV), this term has assumed a broader context and is generally associated with a fiber optic node. This can be defined as those homes or businesses within a specific geographic area that are served from a common fiber optic receiver. A fiber optic node is generally described in terms of the number of "homes passed" that are served by that specific fiber node.

Client

A client is an application or system that accesses a remote service on another computer system, known as a server, by way of a network.^[1] The term was first applied to devices that were not capable of running their own stand-alone programs, but could interact with remote computers via a network. These dumb terminals were clients of the time-sharing mainframe computer.The client-server model is still used today on the Internet, where a user may connect to a service operating on a remote system through the Internet protocol suite. Web browsers are clients that connect to web servers and retrieve web pages for display. Most people use e-mail clients to retrieve their e-mail from their internet service provider's mail storage servers. Online chat uses a variety of clients, which vary depending on the chat protocol being used. Game Clients usually refer to the software that is the game in only multiplayer online games for the computer. Increasingly, existing large client applications are being switched to websites, making the browser a sort of universal client. This avoids the hassle of downloading a large piece of software onto any computer you want to use the application on. An example of this is the rise of webmail.In personal computers and computer workstations, the difference between client and server operating system is often just a matter of marketing - the server version may contain more operating system components, allow more simultaneous logins, and may be more expensive, while the client version may contain more end-user software. There are three types as in thin,fat and hybrid.

Server

In information technology, a server is a computer program that provides services to other computer programs (and their users) in the same or other computers.The computer that a server program runs in is also frequently referred to as a server (though it may be used for other purposes as well).In the client/server programming model, a server is a program that awaits and fulfills requests from client programs in the same or other computers. A given application in a computer may function as a client with requests for services from other programs and also as a server of requests from other programs.Specific to the Web, a Web server is the computer program (housed in a computer) that serves requested HTML pages or files. A Web client is the requesting program associated with the user. The Web browser in your computer is a client that requests HTML files from Web serversAny computer or device serving out applications or services can technically be called a server. In an office or enterprise environment, the network server is easy to identify. A DSL/Cable modem router qualifies as a server because it provides a computer with application services like IP address assignment (via DHCP), NAT, and a firewall that helps protect a computer from external threats. iTunes software implements a music server to stream music between computers. Many home users create shared folders and printers. Another example are the many servers that are used for hosting online games such as Everquest, World of Warcraft, Counter-Strike and Eve Online.

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Input and output

Magnetic ink character-recognition


In computing, a technique that enables special characters printed in magnetic ink to be read and input rapidly to a computer. MICR is used extensively in banking because magnetic-ink characters can be machine-read with much greater accuracy than human reading or other optical character recognition (OCR) systems, and are therefore ideal for marking and identifying the account and sort code numbers on cheques.MICR encodes two very important numbers on the bottom of a check: the American Banker's Association (ABA) routing number and an account number. The ABA routing number, sometimes called an ABA number or just a routing number, uses a combination of codes to indicate the institution where the check was issued. The code, which always totals nine digits, expresses a unique identifier composed of a four-digit Federal Reserve routing symbol, a four-digit ABA institution number and a single check digit. The second set of numbers printed on the bottom of the check represents the bank account number of the associated checking account.


Optical-character recognition


optical character recognition refers to the branch of computer science that involves reading text from paper and translating the images into a form that the computer can manipulate (for example, into ASCII codes).An OCR system enables you to take a book or a magazine article, feed it directly into an electronic computer file, and then edit the file using a word processor.
All OCR systems include an optical scanner for reading text, and sophisticated software for analyzing images. Most OCR systems use a combination of hardware (specialized circuit boards) and software to recognize character, although some inexpensive systems do it entirely through software. Advanced OCR systems can read text in large variety of fonts, but they still have difficulty with handwritten text.
The potential of OCR systems is enormous because they enable users to harness the power of computers to access printed documents. OCR is already being used widely in the legal profession, where searches that once required hours or days can now be accomplished in a few seconds.


Dot matrix printer

A dot matrix printer or impact matrix printer is a type of computer print with a print head that runs back and forth, or in an up and down motion, on the page and prints by impact, striking an ink-soaked cloth ribbon against the paper, much like a typewriter. Unlike a typewriter or daisy whell printers, letters are drawn out of a dot matrix, and thus, varied fonts and arbitrary graphics can be produced. Because the printing involves mechanical pressure, these printers can create carbon copies and carbonless copies.Each dot is produced by a tiny metal rod, also called a "wire" or "pin", which is driven forward by the power of a tiny electromagnet or solenoid, either directly or through small levers (pawls). Facing the ribbon and the paper is a small guide plate (often made of an artificial jewel such as sapphire or ruby) pierced with holes to serve as guides for the pins. The moving portion of the printer is called the print head, and when running the printer as a generic text device generally prints one line of text at a time. Most dot matrix printers have a single vertical line of dot-making equipment on their print heads; others have a few interleaved rows in order to improve dot density.These machines can be highly durable. When they do wear out, it is generally due to ink invading the guide plate of the print head, causing grit to adhere to it; this grit slowly causes the channels in the guide plate to wear from circles into ovals or slots, providing less and less accurate guidance to the printing wires. Eventually, even with tungsten blocks and titanium pawls, the printing becomes too unclear to read.Although nearly all inkjet,thermal, and laser printers print closely-spaced dots rather than continuous lines or characters, it is not customary to call them dot matrix printers.

Platters

One of the disks in a hard disk drive. Each platter provides a top and bottom recording surface. There may be only one or several platters in a drive with each platter having its own pair of read/write heads. When the computers is turned in,these platters will begun to rotate at so many rotations per minute(RPM)This rate varies depending upon the model of hard drive you have; an example of how fast a hard drive may spin is 7200 RPM. As the disk platters are rotating, the read/write head accesses information on one of the platters. To help store and retrieve the data from the platter, data is stored in tracks,sectors and cylinder on each platter.Above is a graphic example of what the inside of a hard disk drive looks like and examples of a hard disk drive platter. As can be seen in the desktop computer hard disk drive this drive has three different platters.

Photo printers


A photo printer is a printer(usually an inkjet printer) that is specifically designed to print high quality digital photos on photo paper. These printers usually have a very high number of nozzles and are capable of printing droplets as small as 1 picoliter.Wireless photo printers use WiFi signals to communicate with your wireless home network. This lets you print to them from any computer connected to the network.It also let you roam around your house with a laptop and still be able to print your photos.Some cameras can communicate to wireless printers directly, so that you don’t need to load the pictures on your computer before you can print them.


Portable printer

Why do you need a portable printer?
If you want to print a variety of documents, your main choices are the all-purpose Hewlett-Packard Deskjet 450 models ($250 to $350) and the Canon Pixma IP90($249). Both print color graphics and text on standard 8.5-by-11-inch paper or images on photo paper.
If you just need to print snapshots, consider a portable photo printer such as HP's Photosmart models ($150 to $200). The Photosmart models are nicely compact, but they don't print anything but 4-by-6 snapshots.
Read "Print Anything, Anywhere You Go," for an overview of what's available.When you take a portable printer on a business trip, you can conveniently print such things as:
Photos of products or real-estate properties to give clients
Web pages to share with colleagues in meetings
PowerPoint presentations for backup purposes (this is particularly important if you revise your presentation on the road)
Driving directions from an online mapping site
Airplane boarding passes
Contracts
Among portable printers, there are differences to consider in functionality, price, size and weight, quality and speed, and accessories.


Multifunctional devices

An MFP (Multi Function Product/ Printer/ Peripheral), multifunctional, all-in-one (AIO), or Multifunction Device (MFD), is an office machine which incorporates the functionality of multiple devices in one, so as to have a smaller footprint in a home or small business setting (the SOHO market segment), or to provide centralized document management/distribution/production in a large-office setting. A typical MFP may act as a combination of some or all of the following devices:
1.Printer
2.Scanner
3.Photocopier
4.Fax
5.E-mail
Many MFP types, regardless of the category they fall in to, also come in a "printer only" variety, which is the same model without the scanner unit included. This is even the case with devices where the scanner unit physically appears to be highly integrated in to the product.


Fax machine


a device that can send or receive pictures and text over a telephone line. Fax machines work by digitizing an image -- dividing it into a grid of dots. Each dot is either on or off, depending on whether it is black or white. Electronically, each dot is represented by a bit that has a value of either 0 (off) or 1 (on). In this way, the fax machine translates a picture into a series of zeros and ones (called a bit map) that can be transmitted like normal computer data. On the receiving side, a fax machine reads the incoming data, translates the zeros and ones back into dots, and reprints the picture.A fax machine consists of an optical scanner for digitizing images on paper, a printer for printing incoming fax messages, and a telephone for making the connection. The optical scanner generally does not offer the same quality of resolution as stand-alone scanners. Some printers on fax machines are thermal, which means they require a special kind of paper.


Internet telephony


A category of hardware and software that enables people to use the Internet as the transmission medium for telephone calls. For users who have free, or fixed-price Internet access, Internet telephony software essentially provides free telephone calls anywhere in the world. To date, however, Internet telephony does not offer the same quality of telephone service as direct telephone connections.
There are many Internet telephony applications available. Some, like CoolTalk and NetMeeting, come bundled with popular Web browsers. Others are stand-alone products. Internet telephony products are sometimes called IP telephony, Voice over the Internet (VOI) or Voice over IP (VOIP) products. In order to use a wireless internet phone, you would need to have a broadband wireless system set up in your home or office. To do this, you would have one computer into which the broadband signal was sent. You would then set up a wireless router, which allowed the signal to be sent from the base computer to other computers in your home. Next, you’ll want to set up the phone system that you’ll be using. You can use a regular telephone, but if you want to go completely wireless there are companies that use a telephone keypad that is displayed right on your computer screen.
You’ll then need to subscribe to an Internet phone provider. There are some companies, such as Vonage, which allow you to make calls to mobile phones and regular landlines. You can also find services that just allow calls from computer to computer.

Telephony


Telephones were originally connected directly together in pairs. Each user had separate telephones wired to the various places he might wish to reach. This became inconvenient when people wanted to talk to many other telephones, so the telephone exchange was invented. Each telephone could then be connected to other local ones, thus inventing the local loop and the telephone call. Soon, nearby exchanges were connected by trunk lines, and eventually distant ones were as well.Digital telephony is the use of digital technology in the provision of telephone services and systems. Almost all telephone calls are provided this way, but sometimes the term is restricted to cases in which the last mile is digital, or where the conversion between digital and analog signals takes place inside the telephone. Telephony was digitized to cut the cost and improve the quality of voice services, but digital telephony was then found useful for new network services (ISDN) to transfer data speedily over telephone lines.
IP telephony is a modern form of telephony which uses the TCP/IP protocol popularized by the Internet to transmit digitized voice data. Contrast this with the operation of POTS (an acronym for "plain old telephone service").
Computer telephony integration (CTI) enables computers to know about ad control phone functions such as making and receiving voice, fax, and data calls with telephone directory services and caller identification. The integration of telephone software and computer systems is a major development in the evolution of the automated office.

SYSTEM UNIT

Expansion Card

It is also know as add-on card,internal card orinterface adapter.An expansion card is an electronic board or card added in a desktop computer or other non-portable computer to give that computer a new ability, such as the ability to connect to another computer using a network cable.There are several types of expansion card such as video card,sound card,network card,modems,POST cards and the others.Generally, around one to seven expansion cards can be installed into the desktop computer system. Laptops do not use standard cards due to their small form factor. Standard interface adapters such as graphics cards and sound cards offer various added functions. Some video cards offer video capture,MPEG 2 and MPEG 4 decoding, light pen and connecting to multiple monitors. Sound cards add functions for composing music, editing audio presentations and other multimedia applications.

Network Interface Card (NIC)

Network interface card is installed in an available slot inside the computer.A network interface controller (NIC) is a hardware device that handles an interface to a computer network and allows a network-capable device to access that network.Network interface cardusually also contains the protocol control firmware and Ethernet Controller needed to support the MAC data link protocol used by Ethernet.

Plug & Play

What is Plug & Play?Plug and Play (PnP) is a capability developed by Microsoft for its Windows 95 and later that gives operating systems users the ability to plug a device into a computer and have the computer recognize that the device is there. The user doesn't have to tell the computer. In many earlier computer systems, the user was required to explicitly tell the operating system when a new device had been added. Microsoft made Plug and Play a selling point for its Windows operating systems. A similar capability had long been built into Macintosh computersWith Microsoft's participation, Plug and Play has been replaced by an open, industry standard, Universal Plug and Play (UPnP), which uses Internet protocols for seamless device plug-in.

Sockets

When a computer program needs to connect to a local or wide area network such as the Internet, it uses a software component called a socket. The socket opens the network connection for the program, allowing data to be read and written over the network. It is important to note that these sockets are software, not hardware, like a wall socket. So, yes, you have a much greater chance of being shocked by a wall socket than by a networking socket.Sockets are a key part of Unix and Windows-based operating systems. They make it easy for software developers to create network-enabled programs. Instead of constructing network connections from scratch for each program they write, developers can just include sockets in their programs. The sockets allow the programs to use the operating system's built-in commands to handle networking functions. Because they are used for a number of different network protocols (i.e. HTTP, FTP, telnet, and e-mail), many sockets can be open at one time.Sockets are commonly used for client and server interaction. Typical system configuration places the server on one machine, with the clients on other machines. The clients connect to the server, exchange information, and then disconnect.
A socket has a typical flow of events. In a connection-oriented client-to-server model, the socket on the server process waits for requests from a client. To do this, the server first establishes (binds) an address that clients can use to find the server. When the address is established, the server waits for clients to request a service. The client-to-server data exchange takes place when a client connects to the server through a socket. The server performs the client's request and sends the reply back to the client.

Chips

The computer chip in the diagram above has several sections that are labelled things like cache, interface, FP control and Integer control, FP multiplier, and datapath. These kind of reflect the types of things involved in microprocessors: memories, interfaces, logic and calculations, and control. The caches, for example, are memories.
A computer chip works by allowing information to enter from the outside world (some of the interfaces), storing the information in the memories (like the caches), doing logical and mathematical operations on the information (like the FP or floating point multiplier), storing the results, doing more logical and mathematical operations on the information, until finally the information is outputted or causes something else to happen (some of the interfaces again). All of these activities need to be controlled (some of the parts labelled "control" may be involved), and this control is generally dependent on other information entered in the computer, called the programming (generally the software).
The information in a computer is stored and operated on (logical and mathematical operations) in digital form - that is, in the form of a set of 1's and 0's. Mathematics on 1's and 0's is referred to as binary arithmetic, and the logical operations are called digital logic.

Slots

What is slots?An opening in a computer where you can insert a printed circuit board. Slots are often called expansion slots because they allow you to expand the capabilities of a computer. The boards you insert in expansion slots are called expansion boards or add-on boards.
Do not confuse slots with bays. Bays are sites within the computer where you can install diskdrives. Typically, slots are in the back of the computer and bays are in the front.

Bus lines
The bus lines are the communicating electronic lines that connect different parts of the CPU to various other parts. In addition, the bus lines also link the CPU to different parts on the system board of your computer. The data flows in the form of bits along the bus lines. The bus lines are like multilane pathway which means that the more bus lines are on the system the greater is the rate of transfer of data along the bus, which means that the computer can run efficiently and will perform the operations at a faster rate.There are several types of bus lines, some of which are as follows, Industry Standard Architecture, the bus line capacity is 16 bit. Though it is slow, it is still being used. Peripheral Component Interconnect has a speed of 64 bit which is being used widely in personal computers. Accelerated Graphics Port is mostly used for acceleration of graphics performance.

Serial part

In computing, a serial port is a serial communication physical interface through which information transfers in or out one bit at a time (contrast parallel port). Throughout most of the history of personal computers, data transfer through serial ports connected the computer to devices such as terminals and various peripherals.In modern personal computers the serial port has largely been replaced by USB and Firewire for connections to peripheral devices. Many modern personal computers do not have a serial port since this legacy port has been superseded for most uses. Serial ports are commonly still used in applications such as industrial automation systems, scientific analysis, shop till systems and some industrial and consumer products. Server computers may use a serial port as a control console for diagnostics. Network equipment (such as routers and switches) often use serial console for configuration. Serial ports are still used in these areas as they are simple, cheap and their console functions are highly standardized and widespread. A serial port requires very little supporting software from the host system.Considered to be one of the most basic external connections to a computer, the serial port has been an integral part of most computers for more than 20 years. Although many of the newer systems have done away with the serial port completely in favor of USB connections, most modems still use the serial port, as do some printers, PDAs and digital cameras. Few computers have more than two serial ports.

Parallel part

Parallel computing is a form of computation in which many calculations are carried out simultaneously,operating on the principle that large problems can often be divided into smaller ones, which are then solved concurrently ("in parallel"). There are several different forms of parallel computing: bit-level, instruction level, data, and task parallelism. Parallelism has been employed for many years, mainly in high-performance computing, but interest in it has grown lately due to the physical constraints preventing frequency scaling.As power consumption (and consequently heat generation) by computers has become a concern in recent years,parallel computing has become the dominant paradigm in computer architecture, mainly in the form of multicore processor.
Parallel computers can be roughly classified according to the level at which the hardware supports parallelism—with multi-core and multi-processor computers having multiple processing elements within a single machine, while clusters, MPPs, and grids use multiple computers to work on the same task. Specialized parallel computer architectures are sometimes used alongside traditional processors, for accelerating specific tasks.
Parallel computer programs are more difficult to write than sequential ones,because concurrency introduces several new classes of potential software bugs, of which race conditions are the most common. Communication and synchronization between the different subtasks are typically one of the greatest obstacles to getting good parallel program performance. The speed-up of a program as a result of parallelization is governed by Amdahl's law.

Universal serial bus

Universal Serial Bus (USB) is a set of connectivity specifications developed by Intel in collaboration with industry leaders. USB allows high-speed, easy connection of peripherals to a PC. When plugged in, everything configures automatically. USB is the most successful interconnect in the history of personal computing and has migrated into consumer electronics (CE) and mobile products.Today, Hi-Speed USB 2.0, provides greater enhancement in performance-up to 40 times faster than USB 1.0, with a design data rate of up to 480 megabits per second (Mbps). In addition, USB On-The-Go (OTG), a supplement to the USB 2.0 specification, was created in 2002. USB OTG defines a dual-role device, which can act as either a host or peripheral, and can connect to a PC or other portable devices through the same connector.
Portable computing devices such as handhelds, cell phones and digital cameras that connect to the PC as a USB peripheral benefit from having additional capability to connect to other USB devices directly. For instance, users can perform functions such as sending photos from a digital camera to a printer, PDA, cell phone, or sending music files from an MP3 player to another portable player, PDA or cell phone.

Firewire post

What is a firewire post?A firewire port is a connection type that is very common in Apple computers, and there are firewire 400s and firewire 800s. Understand what firewire ports are with information from an experienced software developer in this free video on computers.How to locate a pc firewire post?Depending on which type of port is on your computer, you might need a different cable than the one you currently have. The most common scenario for desktop systems is using a 4-pin to 6-pin cable, which connects the 4-pin side to the camcorder and the 6-pin side to the desktop system. FireWire cables also come in 4-pin to 4-pin and 6-pin to 6-pin configurations. As long as you know which connector you have on your PC, getting someone at the local electronics store to point you to the correct cable you need is relatively easy.

Careers in IT

Webmaster

A webmaster is the designation given to the person responsible for designing and maintaning the coding and proper functioning of a website.Webmaster is also called the web architect.The duties of a webmaster include ensuring the web servers,hardware and software are operating accurately,designing the website,generating and rivising web pages,replying to user comment.Webmasters use computer software to do their jobs. They might learn to use many different types of software. Webmasters can also make a website by typing direct instructions in HyperText Markup Language (HTML) or some other programming language.Webmasters and other analysts usually work in offices or computer labs. Some work from home. Sometimes, they work in the evenings or on weekends to solve important problems with a computer system.

Computer support specialist

Computer support specialist help people use computers.When somthing goes wrong,support specialist figure out the problems then they try to fix it.They also install printers,software and other computers tool.Then,they teach people how to use them.Computer specialists may work for the company that makes the computer software or for the place that uses certain computer software, such as a school. They may assist other employees at the company or the customers of that company. They also may be asked by the maker of the software for feedback on good or bad things about the product, since they work with it daily. Most computer specialists work in offices or computer labs. They spend a long time sitting in front of computers. This can strain their back, wrists, and eyes.Computer specialists normally work a 40-hour work week, but that can include being "on call" by phone when they are not on their shift. Some specialists work at night or on weekends

Technical Writer

Technical writing is the presentation of information that helps the reader solve a particular problem. Technical communicators write, design, and/or edit proposals, manuals, web pages, lab reports, newsletters, and many other kinds of professional documents.The first rule of technical writing is "know your audience." Writers who know their audiences well are in a position to suggest and implement solutions to problems that nobody else identifies.Whenever one group of people has specialized knowledge that another group does not share, the technical writer serves as a go-between. But technical writers are not just translators, accepting wisdom from experts and passing it on unquestioningly; they also are in the business of generating truth, by choosing what gets written, and for whom, with the full knowledge that later readers will depend on the accuracy of what has been written.

Software engineer

A software engineer is a person who applies the principles of software engineering to the design, development, testing, and evaluation of the software and systems that make computers or anything containing software, such as chips, work.they are interacting with both business functions and programmers, Software Engineers should have excellent communication skills and should enjoy working as part of a team. They will often have to explain business functions to programmers and technology restraints to non-technical business managers. Software engineer usually requires at least a BS in Computer Science. Should be very familiar with specialized languages relevant to the technologies employed.

Network administrator

Network administrator is a modern profession responsible for the maintenance of computer hardware and software.The Network Administrator is usually the highest level of technical or network staff in an organization and will rarely be involved with direct user support.The actual role of the network administrator vary.It often includes maintenance of network facilities in individual machines, such as drivers and settings of personal computers as well as printers and such. It sometimes also includes maintenance of certain network.Network specialists and analysts concentrate on the network design and security, particularly troubleshooting and or debugging network-related problems. Their work can also include the maintenance of the network's authorization infrastructure, as well as network backup systems.

Database administrator

A database administrator (DBA) is similar to a database developer or designer except that the DBA's key responsibilities is ensuring that a database is available at all to the users and programs that need it. This includes making backups and archiving data. It also includes on-going monitoring to ensure that the database is responding to requests quickly. Sometimes the DBA has some hardware knowledge so that the appropriate servers can be purchased so that the database's performance is not impacted by hardware bottlenecks.Database administrators work in offices or labs. They usually work about 40 hours a week. But evening or weekend work may need to be done to meet deadlines.They must be able to think logically. Being able to concentrate and pay close attention to detail is important. These computer specialists sometimes work on their own, but they often work in teams. They must be able to communicate with computer personnel, such as programmers and managers. They must also communicate with other staff who may have no computer training.They ensure that systems perform as they should and add people to the system as needed. Database administrators often plan security measures. Data integrity, backup, and security are critical parts of the job.They identify user needs, set up computer databases, and test systems.

System analyst

System analyst is the person responsible for the development of an information system. Systems analysts design and modify systems by turning user requirements into a set of functional specifications, which are the blueprint of the system. They design the database or help design it if data administrators are available. They develop the manual and machine procedures and the detailed processing specifications for each data entry, update, query and report program in the system.They develop prototypes of the system along with the users, so that the final specifications are examples of screens and reports that have been carefully reviewed. Experienced analysts leave no doubt in users' minds as to what is being developed, and they insist that all responsible users review and sign off on every detail.

Programmer

Programmer is a person who designs and writes and tests computer programs.Computer programmers write, test, debug, and maintain the detailed instructions, called computer programs, that computers must follow to perform their functions. Programmers also conceive, design, and test logical structures for solving problems by computer. Many technical innovations in programming — advanced computing technologies and sophisticated new languages and programming tools — have redefined the role of a programmer and elevated much of the programming work done today. Job titles and descriptions may vary, depending on the organization.Programmers write programs according to the specifications determined primarily by more senior programmers and by systems analysts. After the design process is complete, it is the job of the programmer to convert that design into a logical series of instructions that the computer can follow.