Parts of a Computer

A Computer is a combination of hardware and software.
Computer hardware comprises of hardware parts and accessories.
Computer software is programs and operating systems that run on the hardware.

Computer Hardware

To summarize, a computer takes input from the user, and then processes the information while optionally storing it, and outputs the result to an output device.
Accordingly we can classify hardware components as follows.

Input Devices
Devices that can accept input from the user.
Processing Device
Components that process the input.
Storage Device
Devices that can be used to store data.
Output Device
Devices that can output data.

Computer Software

Computer software can be broadly categorized into system software and application software.
System Software
System Software refers to programs that run the system environment.
Example: Operating System.
Application Software
Application Software refers to programs that run on top of system software, providing functional capabilities to users.
Example: Word processor, Spreadsheet program etc.

Next: Input Devices