Software is the medium by which a user directs the computer to perform certain task. Software is a collection of programs or procedures designed to perform specific operations. Software can be called as the set of programs, procedures or instructions which are used to operate computer and other related devices. Software in contrast to the hardware is the variable part of your computer.
Software can broadly be classified into application software and system software.
Application software
This is the software that performs all the applications which the user is interested to do. This software directly performs the instructions given by the user. The user can perform one or more specific tasks with the help of application software. Different types of educational software, business software, computer games and automation software used in automation industry are some types of application software. Productivity software such as word processors and spreadsheets, graphic software, CAD and industry specific software are some other types of application software.
System software
These are the programs which support the application software. These are the programs which help you to run the hardware and your compute system. Programs such as operating systems, device drivers, servers, utilities are some types of system software. System software provides an application environment to the application programmer and insulates him from the complex computer programs running behind the scene so that he can perform the tasks.
Some also include programming software in this classification. This is the software which helps the application programmer to device different programs to run specific files or perform specific operations on a computer. The software assists the user to use different programming languages conveniently. There are integrated development environment which help the user to do so. Besides this interpreter, compiler, debugger and linkers are other set of programming software.
Different types of software can be purchased from the market where they are available in CDs or DVDs. They are also available as shareware, freeware, public domain software, liteware and as open source.
Shareware are the software which are available for a limited trial period. This is a type of demonstration software which the user can use for a limited time. Once the time expires the user has to purchase the software for further use. Liteware on the other hand is the software which the user can download to perform certain task. But part of the software remains disabled till you purchase the product.
Freeware is the software which you can freely download but they come with certain copyright restrictions. Similarly the public domain software is the one which you can download freely from different sites and there are no copyright restrictions attached to them.