Hootsuite is a social media management system that allows users to manage multiple social media profiles from one centralized dashboard. It enables scheduling posts across different networks like Facebook, Twitter, Instagram, etc. and analyzing social media traffic and brand mentions. The document provides step-by-step instructions on setting up a Hootsuite account and connecting social media profiles, creating tabs and streams to organize networks, publishing and scheduling posts, installing third-party apps, and using the Hootlet browser extension and mobile apps.