The document discusses three online tools for sharing educational content: YouTube, TeacherTube, and SlideShare. YouTube and TeacherTube allow users to browse, upload, and share video content for educational purposes. SlideShare allows users to create and share online presentations. It is free to join, embed presentations on other sites, and share files both publicly and privately. SlideShare also allows users to participate in contests, sync audio to slides, and create slidecasts.