SlideShare is an online platform for sharing presentations, documents, and videos. It allows users to find and share information publicly or privately. Users can create professional profiles, collaborate with others, and enhance their presentation skills. Instructors can use SlideShare to share course materials with students, create audiovisual presentations through SlideCasts, and encourage live collaboration through features like ZipCast. The presentation outlines several ways SlideShare can be used across disciplines to reinforce content, build interaction, and create an active online learning community.