Introduction to IT

Node
In a network, a node is a connection point, either a redistribution point or an end point for data transmissions. In general, a node has programmed or engineered capability to recognize and process or forward transmissions to other nodes.

Client
A client is the requesting program or user in a client/server relationship. For example, the user of a Web browser is effectively making client requests for pages from servers all over the Web. The browser itself is a client in its relationship with the computer that is getting and returning the requested HTML file. The computer handling the request and sending back the HTML file is a server.

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. In the 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.

Hub
A hub is the central part of a wheel where the spokes come together.In describing network topologies, a hub topology consists of a main circuit to which a number of outgoing lines can be attached, each providing one or more connection port for device to attach to. For Internet users not connected to a local area network, this is the general topology used by your access provider. Other common network topologies are the bus network and the ring network. As a network product, a hub may include a group of modem cards for dial-in users, a gateway card for connections to a local area network. For example, Ethernet, and a connection to a line.

Network Interface Card (NIC)
A network interface card (NIC) is a computer circuit board or card that is installed in a computer so that it can be connected to a network. Personal computers and workstations on a local area network (LAN) typically contain a network interface card specifically designed for the LAN transmission technology, such as Ethernet or Token Ring. Network interface cards provide a dedicated, full-time connection to a network. Most home and portable computers connect to the Internet through as-needed dial-up connection. The modem provides the connection interface to the Internet service provider.

Network Operating System (NOS)
A network operating system (NOS) is a computer operating system system that is designed primarily to support workstation, personal computer, and, in some instances, older terminal that are connected on a local area network (LAN). Artisoft's LANtastic, Banyan VINES, Novell's NetWare, and Microsoft's LAN Manager are examples of network operating systems. In addition, some multi-purpose operating systems, such as Windows NT and Digital's OpenVMS come with capabilities that enable them to be described as a network operating system.

Distributed Processing
Refers to any of a variety of computer systems that use more than one computer, or processor, to run an application. This includes parallel processing, in which a single computer uses more than one CPU to execute programs. More often, however, distributed processing refers to local-area networks (LANs) designed so that a single program can run simultaneously at various sites. Most distributed processing systems contain sophisticated software that detects idle CPUs on the network and parcels out programs to utilize them.

Host Computer
Main or controlling computer connected to other computers or terminals to which it provides data or computing services via a network. It is similar to a server in a client-server architecture. In the modern peer to peer networking every computer is a peer and also a host to every other computer connected to the network. The name reflects the biological relationship between a host and parasites.

Network Manager
NetworkManager is a software utility aimed at simplifying the use of computer networks on Linux and other Unix-like operating systems. NetworkManager is designed in two components: a service which manages connections and reports network changes, and a graphical desktop applet which allows the user to manipulate network connections.

Magnetic Ink Character Recognition (MICR)
Magnetic Ink Character Recognition is a character recognition system that uses special ink and characters. When a document that contains this ink needs to be read, it passes through a machine, which magnetizes the ink and then translates the magnetic information into characters. MICR technology is used by banks. Numbers and characters found on the bottom of checks (usually containing the check number, sort number, and account number) are printed using Magnetic Ink. To print Magnetic Ink need, you need a laser printer that accepts MICR toner.
MICR provides a secure, high-speed method of scanning and processing information


Optical Character Recognition
OCR, 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.



Optical-mark Recognition (OMR)
The technology of electronically extracting intended data from marked fields, such as checkboxes and fill-infields, on printed forms. OMR technology scans a printed form and reads predefined positions and records where marks are made on the form. This technology is useful for applications in which large numbers of hand-filled forms need to be processed quickly and with great accuracy, such as surveys, reply cards, questionnaires and ballots. A common OMR application is the use of “bubble sheets” for multiple-choice tests used by schools. The student indicates the answer on the test by filling in the corresponding bubble, and the form is fed through an optical mark reader (also abbreviated as OMR, a device that scans the document and reads the data from the marked fields. The error rate for OMR technology is less than 1%.


Dot Matrix Printer
A type of printer that produces characters and illustrations by striking pins against an ink ribbon to print closely spaced dots in the appropriate shape. Dot-matrix printers are relatively expensive and do not produce high-quality output. However, they can print to multi-page forms (that is, carbon copies), something laser and ink-jet printers cannot do.





Plotters
A device that draws pictures on paper based on commands from a computer. Plotters differ from printers in that they draw lines using a pen. As a result, they can produce continuous lines, whereas printers can only simulate lines by printing a closely spaced series of dots. Multicolor plotters use different-colored pens to draw different colors.In general, plotters are considerably more expensive than printers. They are used in engineering applications where precision is mandatory.





Photo Printer
A printer specialized for smaller prints such as 4x6" and 5x7". When first introduced in the mid-1990s, photo printers used dye sublimation for high quality printing because inkjet printing was not quite up to par. Since then, inkjet technology has greatly improved, and most photo printers are inkjets. Epson, Canon and HP are major players in this market. See digital camera, photo scanner, inkjet printer and dye sublimation printer.





Portable Printer
Portable printer gives you the freedom to print from nearly anywhere. You can print high-quality documents and photos from your laptop PC, or any number of portable devices, such as PDAs, digital cameras, camera phones, and memory cards.




Fax Machine
A "fax machine" usually consists of an image scanner, a modem, and a printer.Although devices for transmitting printed documents electrically have existed, in various forms, since the 19th century, modern fax machines became feasible only in the mid-1970s as the sophistication increased and cost of the three underlying technologies dropped. Digital fax machines first became popular in Japan, where they had a clear advantage over competing technologies like the teleprinter.

Multifunctional Devices
Multifunctional devices have evolved from photocopiers and have many areas of functionality, predominantly printing, faxing, scanning and integration with other applications.









Internet Telephones
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.



Telephony
It encompasses the general use of equipment to provide voice communication over distances, specifically by connecting telephones to each other.
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.

Expansion card is an electronic circuit board or card that adds more functionality to 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.

It also known as an add-on card, internal card or interface adapter. Expansion cards are installed into the expansion slot of a computer motherboard. Video cards and sound cards are common examples of PC expansion cards. A new video card added will enhance the three dimensional graphics processing power of a computer while a new sound card may improve a computer’s audio input. Laptops do not use standard cards due to their small form factor. A laptop expansion card can be in the form of a removable PCMCIA card that offers additional functionalities to it.



Network Interface Card (NIC) is a computer circuit board or card that is installed in a computer so that it can be connected to an Ethernet network. The card provides an interface to the media.
This may be either using an external transceiver or through an internal intergrated transceiver mounted in the network interface card PCB. Personal computers and workstations on a local area network (LAN) typically contain a network interface card specifically designed for the LAN transmission technology, such as Ethernet or Token Ring. Network interface cards provide a dedicated, full-time connection to a network. Most home and portable computers connect to the Internet through as-needed dial-up connection. The modem provides the connection interface to the Internet service provider.



Plug & Play is a capability developed by Microsoft for its Windows 95 and later operating systems that gives users the ability to plug a device into a computer and have the computer recognize that the device is there. It is a term used to describe the characteristic of a computer bus, or device specification, which facilitates the discovery of a hardware component in a system, without the need for physical device configuration, or user intervention in resolving resource conflicts.


Sockets or slot is an electrical component that attaches to a printed circuit board (PCB) and is designed to house a CPU. It is a special type of integrated circuit socket designed for very high pin counts.
A CPU socket provides many functions, including providing a physical structure to support the CPU, providing support for a heatsink, facilitating replacement and most importantly forming an electrical interface both with the CPU and the PCB. CPU sockets can most often be found in most desktop and server computers, particularly those based on the Intel x86 architecture on the motherboard.



Chips is a small piece of semiconducting material on which an integrated circuit is embedded. A typical chip is less than quarter square inches and can contain millions of electronic components, for example transistors. Computers consist of many chips placed on electronic boards called printed circuit boards. There are different types of chips. For example, CPU chips contain an entire processing unit, whereas memory chips contain blank memory. Chips come in a variety of packages. The three most common are DIPs, PGAs and SIPs.



Slots is an opening in a computer where a circuit board can be inserted to add new capabilities to the computer. Nearly all personal computers except portables contain expansion slots for adding more memory, graphics capabilities, and support for special devices. The boards inserted into the expansion slots are called expansion boards, expansion cards , cards , add-ins , and add-ons. Expansion slots for PCs come in two basic sizes: half- and full-size. Half-size slots are also called 8-bit slots because they can transfer 8 bits at a time. Full-size slots are sometimes called 16-bit slots. In addition, modern PCs include PCI slots for expansion boards that connect directly to the PCI bus.



Bus lines is a set of parallel wires in a computer to which the central processing unit and all input-output units are connected. Each separate wire carries the electric current representing 1 bit. Buses interconnect the parts of the computer that communicate with each other, such as a video card or modem.



The Serial Port is a type of connection on PCs that is used for peripherals such as mice, gaming controllers, modems, and older printers. It is sometimes called a COM port or an RS-232 port, which is its technical name. If that's not enough to confuse you, there are two types of serial ports which is DB9 and DB25. DB9 is a 9-pin connection, and DB25 is, you guessed it, a 25-pin connection. A serial port can only transmit one bit of data at a time.



Parallel Ports is an interface is found on the back of older PCs and is used for connecting external devices such as printers or a scanners. It uses a 25-pin connector (DB-25) and is rather large compared to most new interfaces. The parallel port is sometimes called a Centronics interface, since Centronics was the company that designed the original parallel port standard. It is sometimes also referred to as a printer port because the printer is the device most commonly attached to the parallel port. The latest parallel port standard, which supports the same connectors as the Centronics interface, is called the Enhanced Parallel Port (EPP). This standard supports bi-directional communication and can transfer data up to ten times faster than the original Centronics port. However, since the parallel port is a rather dated technology, don't be surprised to see USB or Firewire interfaces completely replace parallel ports in the future.



Universal Serial Bus Port is a place on the computer where you can attach a cable for connecting a printer, keyboard or moderm. USB is a widely used hardware interface for attaching a maximum of 127 peripheral devices to a computer. There are usually at least two USB ports on laptops and four USB ports on desktop computers. After appearing on PCs in 1997, USB quickly became popular for connecting keyboards, mice, printers and external drives and eventually replaced the PC's serial and parallel ports.


Firewire Ports is a serial bus interface standard for high-speed communications and isochronous real-time data transfer, frequently used by personal computers, as well as in digital audio, digital video, automotive, and aeronautics applications. The interface is also known by the brand names of FireWire (Apple), i.LINK (Sony), and Lynx (Texas Instruments). IEEE 1394 replaced parallel SCSI in many applications, because of lower implementation costs and a simplified, more adaptable cabling system. The 1394 standard also defines a backplane interface, though this is not as widely used.

Nowadays the major influence in most of our lives,at work and at home is Information Techology, IT which is usually involved in the context of a business and is often used to improve the efficiencies in an organisation. By involving computer systems, IT has helped industry reach new markets and apply new services to customers and clients. The developing information technology field there are many different careers, for example, webmaster, computer support specialist, technical writer, software engineer, network administrator, database administrator, systems analyst and programmer.

Firstly, i would like to introduction what is Webmaster. According to my research the definition of Webmaster is a person responsible for maintaining a website(s). The webmasters' duties is to ensuring that the web servers, hardware and software are operating accurately, designing the website, generating and revising web pages, replying to user comment, and examining traffic through the site.

Secondly, Computer support specialist is a job that provide technical assistance to computer system users. their duties is to answer questions or resolve computer problems for clients in person, via telephone or from remote location. In the same time, they may provide assistance concerning the use of computer hardware and software, including printing, installation, word processing, electronic mail, and operating systems.

Thirdly, i would like to cover one of the career in IT which is Technical Writer.
Based on my research, a technical writer is often tasked with writing documentation that explains technical issues in ways that non-technical people can understand. A technical writer might be responsible for writing the how-to manual for a software application. Technical writers are often copy writers and vice-versa.

Fourthly, Software engineer which has generally replaced the term programmer. Software Engineering is intended to mean the processes used to create and maintain software, whether for groups or individuals. This would include subjects like Configuration Management, Project Planning, Project Tracking, Software Quality Assurance, Risk Management, Formal Inspections, etc.

Fifthly, i would like to introduction the career of Network administrator. Network administrator provides technical support and administration of the District Local Area Network (LAN) and Wide Area Network (WAN), assists end users of personal computers with hardware and software problems, and performs other related work as required.For more detail information, you could explore http://careers.stateuniversity.com/pages/218/Network-Administrator.html.

Sixthly, based on the information i get from www.mariosalexandrou.com, a database administrator is similar to a database developer or designer except that a database administrator'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.

Seventhly, a system analyst is the person who selects and configures computer systems for an organization or business. The system analyst's job is to choose the most efficient computer solutions for a business, while making sure the systems meet all the company's needs. The analyst must understand the general objectives of the business, as well as what each individual user's job requires. Once the system analyst has determined the general and specific needs of the business, he can choose appropriate systems that will help accomplish the goals of the business.

Lastly, programmer is the one who would write the code that would run on the client as well as the code that would run on the server. Because the client often had Microsoft Windows installed, there was often less graphic design needed for the user interface because many of the screen elements were standardized.