Computer is an electronic device, which is useful for manipulation of data, calculations, typing of data, data storage and database management. Computer reduces human efforts. Here we can store large number of data & we can filter it as require. Basically computer has 2 main parts.
A)Hardware B)Software
A) Hardware
Hardware means physical parts of computer, which we can see & we can touch. Input devices & output devices are part of hardware. We feed data into computer through input devices. We get result which we want, through output devices.
1) Input & output devices are as follow:
i)Monitor – Monitor is a device, where we can see data, pictures, text etc. This is output device. Monitor comes in various ranges & various resolutions.
ii)Printer – Printer is an output device. It gives prints of required documents. There are mainly 3 types of printers. A) Dot matrix 2) Ink jet 3) Laser
iii)Speakers – we can attach speakers to computer. Speakers are output devices. We can hear songs through it.
iv)Keyboard – Keyboard is an input device. We can type through keyboard.
v)Mouse – Mouse is an input device. It is pointing device. We can select menus, tools etc. through mouse. Mainly mouse has 2 buttons. 1) Left click button 2) Right click button. Left click button is generally used for selection and right click button is used for shortcut selection like copy, paste etc. 3rd scroll button is available for scrolling of pages.
2) Central Processing unit
Calculations, Storage of data, Data processing etc. is done in this unit. It has motherboard, Hard disk, CD drive, USB drive, RAM, ROM, Bus lines and many electronic circuits.
3) Storage Devices
1)Hard disk – It is internal storage device. It can store large amount of data, generally in GB (Gigabytes). It is permanent storage device. We cannot remove it from one computer to another.
2)Floppy Disk – It is an external storage device. It has small capacity. It is removable device. We can copy data from one computer to another through this. Now a day's Floppy disk is not in use.
3)Compact Disk – Now this storage device is used. It is removable device. CD drive is required for this.
4)USB – This is also removable storage device. We can copy data from one computer to another by using this device.
5)Memory card – Generally it is used for Mobile phone data storage. But using Card reader we can use it for computer as external storage device.
B) Software
Software means programs made according to use. There are main 2 types of software
1)Application software – These are used for specific task. MS Word is application software. It is used for word processing. MS excel, MS PowerPoint, MS Access are examples of application software. MS Excel is used as a spreadsheet. PowerPoint is used for presentation.
2)System Software – Operating systems, device drivers etc. are handled by System Software. Windows, UNIX, Linux are operating systems. These are example of System Software