speech at a conference. One or more authors create a blog with text, images or videos and design the look and feel. Readers can comment on or rate each of the blog entries, depending on the permissions or rules applied. Online group discussions where people have conversations about a topic, share ideas or ask specific questions. Common uses are product support or interest based discussions. Collaborative documents that help people create content with text, images and video. Wikis are often used for documentation, FAQs or articles. Because wikis can have multiple authors, versions of wiki articles are tracked, as well as a history of changes, for future reference.