Microsoft Teams is Microsoft's unified collaboration platform that combines persistent chat, video meetings, file storage, and app integration into a single hub for modern workplace communication. Launched in 2017 as part of Microsoft 365, Teams replaced Skype for Business and has become central to hybrid and remote work strategies. The platform operates on a team-channel-chat hierarchy where teams contain channels (standard, private, or shared), and each interaction ties to SharePoint for storage and OneDrive for personal files. The key mental model: teams are containers, channels are topics, chats are conversations—understanding this structure prevents the common mistake of creating too many teams when channels would suffice.