A wiki is a collection of web pages that allows users to collaboratively add, edit, and modify content easily without requiring HTML knowledge or specialized software. Wikis enable many people to work together on pages simultaneously, with past edits recorded but not separate versions kept. They are well-suited for collaborative work that remains open and evolving. In contrast, blogs are owned by a single author and allow others only to comment rather than edit the content directly. Examples of wikis include Wikipedia, library staff documentation wikis, and subject guide wikis for library users.