1. Hardware and Software
Hardware refers to the physical devices of the computer system e.g. monitor, keyboard, printer, RAM etc.
Software is a set of programs, procedures and associated documents to perform a specific type of job e.g. word processing software contains programs for text editing, formatting etc.
Both are mutually dependent .
Software acts as interface between user and hardware.
Two types of software:
System Software
Application Software.

2. System Software
Set of one or more programs designed to control the operations of a computer system.
The programmers who prepare system software are called system programmers.
Supports development of other application software.
Monitors effective use of various hardware resources such as CPU, memory, etc.
Communicates with and controls operation of peripheral devices.

3. Commonly used System Software
Operating Systems: Acts as resource manager.
Programming language Translators: Transform the instructions prepared by programmers in high level language into a form that can be interpreted and executed by a computer system e.g. Assembler, Compiler, Interpreter.
Utility Programs: A Set of programs that help users in system maintenance tasks such as formatting of hard disks, taking backup of files etc.

4. Application Software
A set of one or more programs designed to do specific task.
Programmers who prepare application software are called application programmers.
Close to user.
Machine independent.

5. Common application software
Word-Processing Software: For creating, editing, viewing, formatting and printing documents e.g. MS-Word
Spreadsheet Software: Numeric data analysis tool that allows us to create computerized ledger e.g. MS-Excel
Database Software: For creating and maintaining databases e.g. MS-Access
Graphics Software: For creating, editing, viewing, formatting and printing pictures, graphs, drawings etc e.g. Coreldraw
Entertainment & Educational Software: Computer to be used as teaching and learning tool.

6. Firmware
Firmware is software substituted for hardware and stored in read only memory.
This technology has enabled production of various types of smart machines having microprocessor chips with embedded software.