A wiki is a server program that allows users to collaborate in forming the content of a Web site. Wiki allows anyone to edit, delete or modify content that has been placed on the Web site using a browser interface, including other users' contributions.

Wikis are known as the tool of choice for large, multiple-participant projects. Visitors can also create new content and change the organization of existing content. The prime example of a wiki in action is Wikipedia, the open source encyclopedia. Wikipedia builds on transparency, simple linking, and a lot of people being involved in editing and authoring.

Things to know about Wiki:
• collaborative Web site
• every page can be edited by anyone. It is not necessary to know HTML (hypertext markup language) or perform work in HTML code
• simple mechanism for creating new pages
• formatting is being done through a simple text language inside the text every version of hypertext is stored and versions can be compared
• linking is done automatically on the server-side
• all pages are stored in a database. At any time, contributors can conveniently view the Web page as it looks to other subscribers, before and after the changes they have made
• wiki provides a simplified interface.