Software

Packaged Software
A packaged software refers to computer software packaged in an archive format to be installed by a package management system or a self-sufficient installer. Linux distributions are normally segmented into packages. Each package contains a specific application or service.

Examples: Open Office, Microsoft Office, a library for handling the PNG image format, a collection of fonts, or a web browser.

Custom Software
Custom software is a type of software that is developed either for a specific organization or function that differs from or is opposite of other already available software. It is generally not targeted to the mass market, but usually created for companies, business entities, and organizations. Custom software is also when companies or governments pay for customized software for budget or project managing. Non-commercial custom software development is common in academic and open source circles.

Examples: Commercial products such as commercial websites, business databases and software for governments

Shareware
The term shareware refers to copyrighted commercial software that is distributed without payment on a trial basis and is limited by any combination of functionality, availability, or convenience. Shareware is often offered as a download from an Internet website or as a compact disc included with a periodical such as a newspaper or magazine. The aim of shareware is to give buyers the opportunity to use the program and judge its usefulness before purchasing a license for the full version of the software.

Examples: Games demo, video converter with limitation.

Freeware
Freeware is computer software that is available for use with no cost or for an optional fee. Freeware is often made available in a binary-only, proprietary form, thus making it distinct from free software. Freeware allows authors to contribute something for the benefit of the community, while at the same time allowing them to retain control of the source code, future direction of development and preserve its business potential. Freeware is different from shareware, where the user is obliged to pay (e.g. after some trial period or for additional functionality).

Examples: Avast Home Edition, notepad++, Google SketchUp, Winamp.

Public Domain Software
Public domain software is software that is not copyrighted. If the source code is in the public domain, that is a special case of non-copylefted free software, which means that some copies or modified versions may not be free at all.

In some cases, an executable program can be in the public domain but the source code is not available. This is not free software, because free software requires accessibility of source code. Meanwhile, most free software is not in the public domain; it is copyrighted, and the copyright holders have legally given permission for everyone to use it in freedom, using a free software license.

Example: Open source software such as Linux and OpenOffice.