Wikipedia:Contributing to Wikipedia

Wikipedia's purpose

A short video about that "Edit" button and what it can do when you are bold! (1:06 min)
Further information: Wikipedia:What Wikipedia is not

Our purpose is to create a web-based, free content encyclopedia of all branches of knowledge, in an atmosphere of mutual respect and cooperation. The goal of a Wikipedia article is to create a comprehensive and neutrally written summary of existing mainstream knowledge about a topic. Editors are encouraged to be bold in editing in a fair and accurate manner with a straightforward, just-the-facts style. Articles should have an encyclopedic style with a formal tone. Instead of essay-like, argumentative, or opinionated writing. The five pillars is a popular summary of the most pertinent Wikipedia principles.