Communication and Network

Twisted pair :
A cable composed of two small insulated conductors twisted together without a common covering.


Coaxial cable :
Consists of an outer conductor and an inner conductor separated by an insulating plastic filler. Usually,these two conductors usually carry equal currents in opposite directions,some of the examples are cable TV hookups and also certain types of computer networks.

Fiber-optic cable :

A technology that uses glass or plastic, threads (fibers) to transmit the data.A fiber optic cable consists of a bundle of glass threads, each of which is capable of transmitting messages to modulate onto light waves.


Node :
In a communications system, a node is a network junction or connection point. Every terminal, computer, hub and switch is a node.But,in database management, a node is an item of data that can be accessed by two or more routes.


Client :

The customer of a vendor or consultant. The client of an IT department is the end user.At the same time,it also refer like a user's computer, which is generally a Windows, Mac or Linux desktop or laptop. The term implies that the client machine is connected to a network

Server :

A server is an application running on a computer that delivers a service and the way a server and a client dialogs is called a protocol

Hub :
It is important place because its facilitating movement or transportation whilst supporting a load, or performing labor in machines

Network Interface Card (NIC) :

In computer networking, it provides the hardware interface between a computer and a network.

Network Operating System (NOS) :

An operating system that contains components and programs that allow a computer on a network to serve requests from other computer for data and provide access to other resources such as printer and file systems

Host computer :
The host computer is used to run the debugger.

Network manager:
Refers to the broad subject of managing computer networks.Some of the examples are...

Performance: Eliminating bottlenecks in the network.

Reliability: Making sure the network is available to users and responding to hardware and software malfunctions.

Second Storage

Disk caching :

A temporary storage area where frequently accessed data can be stored for rapid access. Once the data is stored in the cache, it can be used in the future by accessing the cached copy rather than re-fetching or recomputing the original data.

Redundant arrays of inexpensive disks (RAID) :

Organization of multiple disks into a large, high performance logical disk.

Disk arrays stripe data across multiple disks and access them in parallel to achieve:-
(i) Higher data transfer rates on large data accesses

(ii) Higher I/O rates on small data accesses.

Data striping also results in uniform load balancing across all of the disks, eliminating hot spots that otherwise saturate a small number of disks, while the majority of disks sit in is original.

File compression and decompression :

Image compression is minimizing the size in bytes of a graphics file without degrading the quality of the image to an unaccceptable level. The reduction infile size allows more images to be stored in a given amount of disk or memoryspace

Input and Output

Magnetic Ink Character Recognition(MICR) :

A tool that commonly used in banking area,the technology itself allows the computers to read information (such as account numbers) off of printed documents.

Optical-Character Recognition(OCR) :

The mechanical or electronic device translation of images handwritten, typewritten or printed text into machine-editable text.

Optical-Mark Recognition(OMR) :

It is defined as a scanner device that shines a beam of light onto the form paper. This is because the contrasting positions on the page is utilized to detect the marked are due to reflection of less light than the blank areas of the paper.

Dot-matrix printer :

A computer type printer with a print head that runs in four side(back,front,up and down) on the page with the help of inks .Besides that,the dots,is produced by a tiny rod called a "wire" or "pin", which is driven forward by the power of tiny electromagnet.

Plotter :

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.

Photo printer

Commonly it used to print out a high quality photos on a photo paper.

Portable printer :

It is wireless printer that can straightly print out the picture from the digital camera.

Fax machine :

The design just like a normal house telephone but slightly different in sense that this device can transfer a copy of documents including the picture too but using a certain number or code to transfer it.

Multifuntional device :

Multifunctional devices bring the worlds of copying, printing, finishing, and scanning together, all in one neat, using one device without costing you a lot of money.

Internet telephones :

An instrument that converts voice and other sound signals into a form that can be transmitted to remote locations and that receives and reconverts waves into sound signals.Example Skype,Yahoo Messenger and Windows Live Messenger.

System Unit

Expansion card:
Also known as an add-on card, internal card or interface 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. Examples like video card,modem,video capture card.

Network interface card:

Specially desinged for certain type of netwotk such as protocol,network,and media even some of it can do the multiple task work

Cache memory:

It is an extremely fast bulit in memory inside the computer program system or located next to it on separate chips


Plug&play:

In computing, plug and play is a term used to describe the characteristic 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.Plug and play also refers to both the traditional boot-time assignment of device resources and driver identification.


Sockets:

in computing area:-

Internet socket, an end-point in the IP networking protocol
CPU socket,, the connector on a computer's motherboard for the CPU
Unix doamin socket, an end-point in local inter-process communication

Chips(computer chips):

A 3D cube of chips, using bare chips mounted one over the other with spacers in between. As this technology matures, it is expected that up to 100 chips can be used in one cube.

Slots:

An opening in a computer where a ciruit board can be inserted to add new capabilities to the computer.

Buslines:

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.

Serial port:

In computing, a serial port is a serial communication physical interface through which information transfers in or out one bit at a time . Throughout most of the history of personal computers, data transfer through serial ports connected the computer to devices such as terminals and various peripherals.

Parallel port:

A type of interface found on computers for connecting various programme.Also knowm as a printer port or Centronics port.

universal serial bus

Universal Serial Bus (USB) :

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.

Firewire port

It is a ports to forms a serial port that make use the firewire port technology to transfer data rapidly from one electronic device to another.

The Internet,The Web and Electronic Commerce

HTML: stands for Hyper Text Markup Language to describes web pages.


Javascript: is a programmed language that been used in the web.


Applets: it is a small application with one specific task.


Business-to-Consumer E-Commerce: the buying and selling of goods and services on the internet with you and the computer.


Consumer-to-Consumer E-Commerce: involve all the transactions between the
consumer where they promote new things or product every month


File Transfer Protocol(FTP): a method of moving files between two Internet sites.


Filters: a tool that removes something from anything passes through it .

Careers in IT

Careers in IT

(1) Webmaster-

An individual who manages a web site. Depending on the size of the site, the webmaster might be responsible for any of the following such as designing the website,creating and updating web pages .

(2) Computer support specialist-

In other words,they will help the customer solve the difficulties in managing the computer.

(3) Technical writer-

The person responsible for writing hardware and software documentation, online help, technical definitions and technical product descriptions on Web sites.

(4) Software engineer-

Software Engineering" has been used to describe "building of software systems which are so large or so complex that they are built by a team or teams of engineers", as was used in

(5) Network Engineering-

A modern profession responsible for the maintenance of computer hardware and software that comprises a computer network.

(6) System analyst-

Computer systems analysts start their work by asking people what they need their computers to do and interpret the data for us.

(7) Programmer-

A programmer is someone who writes computer software.On the other hand,the term computer programmer can refer as a specialist or to generalist who writes code for many kinds of software.

(8) Database administrator-

Essentially, the main role of a database administrator has to do with overseeing the installation and ongoing function of software on a system designed for use by a number of users.