Slideshare is a platform that allows users to upload presentations and slideshows that can be viewed and shared by others. Users can sign up with Facebook, LinkedIn, or by providing an email and password. Once signed up, users are directed to the homepage where they can find suggestions on popular members and topics to follow. Slideshare is useful for both personal and business purposes - businesses can view strategies and get ideas, while individuals can showcase their work, gain exposure, and connect with others.