Computer & It's Component

Computer is An electronic device that stores, retrieves,and processes data, and can be programmed with instructions. A computer is composed of hardware and software, and can exist in a variety of sizes and configurations. The term hardware refers to the physical components of your computer such as the system unit, mouse, keyboard, monitor etc. The software is the instructions that makes the computer work. Software is held either on your computers hard disk, CD-ROM, DVD or on a diskette (floppy disk) and is loaded from the disk into the computers, or  RAM (Random Access Memory), as and when required.

Input Devices or How to tell it what to do. There are some input devices in computer, they are keyboard, mouse, tracker balls, scanner, touch pads, light pens and joystick. The Mouse is Used to ‘drive’ or pointer in computer.The keyboard is still the commonest way of entering information into a computer. Tracker Balls is an alternative to the traditional mouse and often used by graphic designers. A scanner allows you to scan printed material and convert it into a file format that may be used within the PC. Touch Pads is a device that lays on the desktop and responds to pressure. Light Pens is used to allow users to point to areas on a screen and Joysticks used to Many games required for the proper playing of the game.

Output Devices or what the result of computer. There are some output devices at computer, they are monitor, VDU, plotter, speakers, and Speech synthesisers . The monitor (the screen) is how the computer sends information back to you. VDU or The computer screen is used for outputting information in an understandable format. Printers is used for print document at computer. There are many different types of printers. In large organizations laser printers are most commonly used due to the fact that they can print very fast and give a very high quality output. Plotter is an output device similar to a printer, but normally allows you to print larger images. Speakers is used for Enhances the value of educational and presentation products or a media where is the sounds from computer out. Speech synthesizers, gives you the ability to not only to display text on a monitor but also to read the text to you.

Storage Devices -- "How it saves data and programs“. There are many storages media, is it used for save data and program. Computer needs storage devices to remember all the input data from brainware . there are several media for storage devices.  Hard disk drives are an internal, higher capacity drive which also stores the operating system which runs when you power on the computer. "Floppy" disk drives allow you to save work on small disks and take the data with you.

Memory -- "How the processor stores and user immediate data“. When the data have been save at storage devices, we need memory to remember it again and to open the data before. There are two memory that existed at computer, RAM and ROM.  RAM - Random Access Memory is the main 'working' memory used by the computer. When the operating system loads from disk when you first switch on the computer, it is copied into RAM. As a rough rule, a Microsoft Windows based computer will operate faster if you install more RAM. Data and programs stored in RAM are volatile (i.e. the information is lost when you switch off the computer). ROM – Read Only Memory as the name suggests is a special type of memory chip that holds software that can be read but not written to. A good example is the ROM-BIOS chip, which contains read only software. Often network cards and video cards also contain ROM chips.