To run your computer system, what types of software are necessary ? What role does each type play in computer's functioning ?

To run our computer system, the following two types of software are necessary:

1. System Software — This type of software controls internal computer operations. The system software can further be classified in two categories:
   
   1. Operating System — An operating system is a program which acts as an interface between a user and the hardware. For example, Microsoft Windows 10, Linux OS.
   2. Language Processor — This program is responsible for converting an HLL code (High Level Language code) into machine understandable code. For example, interpreter and compiler.
2. Application Software — An application software is the set of programs necessary to carry out operations for a specified application. For example, Microsoft Word, Adobe Photoshop etc.