SlideShare is a website for sharing presentations that has over 55 million monthly visitors and 120 million page views. Users can upload PowerPoint files, videos, documents and more to share content. Presentations can be shared on social media or embedded on other sites. Various account types are available, including free basic accounts and paid PRO accounts with more features like private sharing and premium video uploads. The document provides instructions on how to sign up for an account and upload PowerPoint files to SlideShare to share with others.