Microsoft Teams is a unified communications platform that combines persistent workplace chat, video meetings, file storage, and application integration. The service integrates with the company's Office 365 subscription office productivity suite and features extensions that can integrate with non-Microsoft products. Microsoft Teams is a competitor to services such as Slack and is the evolution and upgrade path from Microsoft Skype for Business.
Teams is central to the logical architecture of productivity services in Microsoft 365 - including data governance, security, and compliance capabilities. (PDF)