This document discusses various multimedia formats that can be used on the web, including plug-ins, codecs, and embedding options. It notes that while plug-ins expand web capabilities, they can cause compatibility and security issues. Common multimedia formats are described, such as Flash video, QuickTime, Windows Media, and audio formats. Design considerations for using multimedia are provided, such as not surprising users, previews, and explaining plugin requirements. Methods for embedding Flash video and slideshows are also outlined.