Electronic instructions that tell your computer what to do. Without software, a computer is like an airplane without a pilot. There are two types of software: operating system software and application software. Operating system software (e.g., MS-DOS, Windows) sets the rulesfor how computer hardware and application software work together. Application software (e.g., Word, Lotus 1-2-3) helps you to write letters, analyze numbers, manage finances, draw pictures, and even play games.
