Networks & Communications

Node
A node is a "connection point" in a network. It is either the distribution point or the end point of for data transmissions. A node is programmed to transfer, process as well as receiving transmissions to/from the other nodes. The modem, router, hub, or bridge is made up of a programme of network nodes .

Client
A client is a browser where a user requests for pages from the servers across the web. In other word, a Client is a system that accesses a remote service on server. Clients are also classified under 3 main categories, they are Fat Client, Hybrid Client, and Thin Client.

Server
A server is a programme running in a computer that handles requests for browsers. At the same time, they provide services for their users from other computers. Also, any devices or computers sending out information or services can be called as a Server. A server is famous for its use to host online games or LAN games.

Hub
A hub is a connection point between the devices in a network. A hub contains multiple ports that are used to connect the Segments in a LAN. They also connect multiple twisted pair or fibre optic Ethernal devices together so that they could work as a single network segment. There are 3 main types of hubs, a passive hub, a active hub, and an intelligent hub.

Below is a diagram of a client-server.

Network Interface Card (NIC)
It is an expansion board that users insert into the computer system so that the computer can connect to the network. It is usually called NIC or a network card. Most NICs are designed for a particular type of network, protocol, and media.
an expansion board you insert into a computer so the computer can be connected to a network. The card communicates with the central wireless switch or hub via radio waves.

Below is an image of a Network Interface Card (NIC)

Network Operating System (NOS)
A NOS is a system that connects the computer and devices to the LAN. The system supports workstation, personal computer, and also some older terminals. Some example of NOSs are Netware and Microsoft LAN's Manager. They provide printer sharing, common file system, and also database sharing as well as application sharing. Also, they have the ability to manage a network name directory and also its security.

Distributed Processing
Distributed Processing means that a computer system uses more than one computer or processor to run applications. An example is the parallel processing in which a computer contains more than 1 CPU to execute its programmes. Most of these systems contain sophisticated software that detects idles on the network and then parcels out programmes to solve them.

Below is an image of a Distributed Processing, where a computer uses more than 1 processor/CPU to run its applications.

Host Computer
A Host Computer is a computer that is attached to a network, and then provides services like acting as a store-and-forward processor or communication switch. It acts as the main computer connected to the other computers to which it provides data or computing services via a network. It is very similar to a Server.

Network Manager
It is also known as the Network Administrator. It is a software ultility aimed at simplifying the uses of computer networks. Also, it ensures the network's security, performances and also the reliability. It works by collecting counterparts and data for LAN Network Manager. It is developed by Microsoft in cooperation with 3Com Corporation.

Input and Output

Magnetic Ink Character Recognition (MICR)
It is a character recognition system that uses specialized ink, symbols and characters which can be magnetised and read automatically and then be printed out rapidly. It is widely used in banks to print the details on cheques. Reason being the magnetic-ink character can be read under greater accuracy. Each character will produce an unique waveform that can be easily identified only by the computers.



Image of an MICR Reader



Image of the codes and characters






Optical-character Recognition (OCR)
It is a computer-science that reads text from papers and translate the image into a form of data that the computer can manipulate. For example, you can take 1 page of article from a hardcopy and transfer it into datas to computer system for further editting using a word software or etc. I.e: Optical Scanner
Advanced OCR can read text in many types of fonts. However there are still difficulties in reading handwritten texts.


Image of an OCR Reader






Optical-mark Recognition (OMR)
It is a technology where data is extracted electronically from check boxes, fill-in fields, on printed forms. Different from an OCR, a recognition engine is not required. Therefore, this will require the image or text to have higher contrast so that it can be easily recognized. This technology is very fast and can be used in a variety of application. I.e, business reply mail, surveys, verification of signatures.



Image of an OMR Reader



Image of a form




Dot Matrix Printer
It is a kind of printer that produces characters or illustrations by strinking pins against an ink ribbon, to print the closely-spaced dots to produce characters. These kind of printers are expensive and do not produce high quality output. However, they can print multiple pages forms that sometimes a bubble-jet printer or laser printer cannot do. The Dot Matrix Printer is measured in 2 different characteristics that are the speed and the print quality.



Image of a Dot Matrix Printer and its output character.




Plotters
It is a kind of printer that interprets commands from a computer to make line drawings and adjustments on paper with an automated pen. It can also draw contineous point-to-point lines from graphic files. The operating rate is very slow because of the mechanical movement of the drawing pens. They can produce high resolution vector-based outputs as well as creating very large drawings.



Image of a Plotters





Photo Printer
A photo printer is usually the printer that is designed to produce high quality digital photographs. These printers usually contain a lot of nozzles that are used to spray printing droplets as small as 1 picoliter. Unlike standard inkjet printers, photo printers can print images that is taken directly from the camera that supports the PictBridge protocol. Popularity of this printer has increased over the extensive use of digital cameras.


Image of a Photo Printer




Portable Printer
This kind of printers are small, light and portable. They are designed for travellers or those who needs to work while "on the go". This design is aiming at its conveniency of digital photography. Travellers can just snap a photo, plug the camera in to the printer, and then print them out straight away in very fine quality.


Image of a Portable Printer connected to a Digital Camera.





Fax Machine
It is a device that can send and receive text or images over a telephone line. It functions by dividing the text medium into little grid of dots. Each dot is represented by the bit that has a value which is 1(off) or 0(on). The "Off" and "On" determinds the output colours whether they are in black or white. A series of codes translated by the system into readable data are called a "bit map". On the receiving side, they receive the data and translate them back into human-readable images or text and then print them out.



Image of a Fax Machine





Multifunctional Devices
It is the kind of printers that are designed for greater working efficiency. The functions of scanning, copying, printing and faxing are clamped together into one printing device so that it allows user to save money on other compartments. This kind of printers can help users to save space too. The price of these printers are low and affordable, but the performances are good enough because it can perform a huge range of multifunctional colour printings.



Image of a Multifunctional Devices





Internet Telephones
An Internet Telephone service uses the Internet instead of the traditional phone lines to send voice over the receiving end(s). Phone lines are plugged into the computer and users can communicate via the headphone that is plugged into the USB slot. This Internet Telephone service can help to save money and at the same time allows the customer to enjoy better calling features and qualities. The calls can be extremely cheap or even free to anywhere in the world.


Image of an Internet Telephone connected with the USB cable.





Telephony
It is a technology associated with the electronic transmission of voice, fax and other information between long distant parties using a handheld device containing both speaker and transmitter as well as a receiver. It contains the function of sending voice messages along with text e-mails. Fax transmissions can also be sent at a very low cost.


Image of a Telephony Network



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System Unit. (Error 666. Please run exorcism.exe immediately)

Expansion Card
It is a printed circuit board that is inserted into an expansion slot of a motherboard. The main function of a Expansion Card is to provide the function other than that a motherboard can offer. Below are a few examples of expansion cards.



i) Network card






ii) 3D Card







Network Interface card (NIC)
It is also known as the Network Card. It is a device that allows computers to be joined together via LAN. Using a given and specific protocol, the network computers are able to communicate together. For dial-up Internet user, the telephone line is usually plugged into the slot of the Network Interface Card. All the computers in the computer labs, and cyber cafes joined their computers in a network by using this device.



Plug&Play
It is a system capability developed by Microsoft initially for Windows95, or newer operating systems. It gives its user the ability to plug a device into the computer system and have the computer to recognize that the device is there without having to manually setting the device up. Before the invention of the Plug and Play, users are required to tell the operating system that a particular new device is installed.



Sockets
It is a piece of plastic or metal contacts made for each of the pins in the CPU. It is to physically protect the CPU. It also connects the electrical circuit between all the pins and sockets inside the CPU.

Image of a socket





Chips
It is a small electrical circuit, also known as the intergrated circuit. It is a kind of basic electronic component of all kinds of electronics, especially the computers. The computer chips are made of semiconductors that consist of silicons and other component including the transistors. Today, a computer chip can contain millions of transistors and that help the computer in becoming smaller and more powerful.



Slots
Slots are oftenly called Expansion Slots. They are basically the holes that are used as a place where external devices are plugged into the computer(sound card, video card, etc). These external devices are called expansion boards. The external features being installed can expand the capability of an original computer. Some examples are the USB slot.




Bus Lines
The Bus Lines are the communicating electronic lines that connect different parts of the CPU to various other parts as well as the system board of the computer. The data flows in the form of "Bit" in a bus line. The bus lines are the electronic pathway that decide the rate of transfer of data. The greater the bus lines, the better the efficiency of the computer.



Serial Port
A serial port is a port that can be used for serial communication, where only "1 bit" allowed to be transmitted at a time. A serial port can be used for almost any types of devices including the modem, mouse, and printers. The data is transmitted through the serial ports connected to the computer to the other devices and other various perispherals.

Image of a Serial Port





Parallel Port
It is also known as the Parallel Interface, initially for connecting External devices such as the printer, external hard disc, joystick, which relatively needs a higher bandwidth. The Parallel Port is already being replaced by the USB port and they are no longer needed for printers.



Universal Serial Bus
More oftenly known as the USB. It is an external bus standard that supports data transfer rate of 12Mbps. It is now commonly used for external devices like mouse, printers, laptop coolers,pendrives, etc.

Image of a USB slot and cable





Firewire Port
It is a kind of serial port that is used to transfer data rapidly from one electronic device to another. 1 example is to transfer files from the digital camera or camcorders to the computer. The transfer rate of a Firewire Port can reach up to 400Mbps. The data transfer rate is relatively fast and the quality is also excellent.

Image of a Firewire Port and the cable

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Guitar Poster(framed)






Guitar Amplifier






Heroes Necklace(rusted)






PS2 DvDs





Assorted Reading Meterials

Careers in IT

Webmaster
The webmaster is usually the main developer of a certain website. They are usually HTML experts who manage the operation and administration of the website. They are in charge of managing the website servers, layouts, content and so on. Some webmasters are also in charge of scripting and configurating.


Computer support specialist
A computer support specialist works mainly inside a company while they also provide in-house services to their customers. They help to take care of all the mechanical and technical problems. They are mostly asked to answer inquiries about certain softwares or hardwares. Therefore, a computer support specialist must have good communication and problem-solving skills.

Technical Writer
Technical writer composes and handles manuals and user-guides for their products. The documentation a technical writer produced must be accurate and comprehendible in order to aid their consumers to use the products correctly.

Software engineer
Software engineers are in charge of developing software system of the certain product. They also modify some of the existing programmes to maintain their working performances. The field of responsibilities of a software engineer is very vast - from testing and trouble-shooting new software programmes to operational documentation writting. It is one of the most popular careers in IT in terms of the numbers of employment.

Network administrator
The network admin is a profession that manages the networking system of a company. Their job targets mainly on the health and security issues of the network in the company, which also includes the routing of protocools and some network address configuration. Their main responsibility is to administrate LAN/WAN to ensure its well performance.

Database administrator
The job of a database admin is to ensure that the security and the performance of the existing data. They are to make sure that the data remains consistent, organized, and clearly defined. In certain cases, the database admin will be called upon to explain and analyze the stored databases to make recommendations relating to the performance efficiency.

System analyst
System analysts answer the enquiries of their customers by asking them what they need their computers to do, and then design a system that can fullfil their customers' need for the computer. They also suggest their customers on what to purchase as well as telling the software programmers how to make new softwares that are needed.

Programmer
Naturally, programmers usually deal with programmes. They code a series of instructions for the computer by using coding languguages such as COBOL, Prolog, Java, and so on. This leads to a wider extention of programmer's profession such as Java Programmers, based on the languguage they are familiar with. Other than that, a programmer also tests a programme by running it to ensure the desired outcome. If errors occur in between, then they begin the debugging process.