A free encyclopedia with millions of articles contributed collaboratively using Wiki software, in dozens of languages. An overview is a survey of what is covered or included in an area. Overviews of Wikipedia's coverage include:

Outline of knowledge - Wikipedia's outline of the knowledge of humankind (still under development) also serves as a general site map of Wikipedia's contents. It is composed of topic outlines (one for each subject), and each of these pages presents its subject's structure, with links to the topics that make up its subject.

Overviews - a one-page summary of the contents of Wikipedia, presenting an overview of 12 major subjects, providing links to key articles in each.

List of academic disciplines - Wikipedia arranged like a college course curriculum.