Microsoft Visual Studio Team Services (VSTS), now known as Azure DevOps Services, was a cloud-based extension of the Visual Studio platform. It provided an integrated set of tools for software development teams to collaborate on code development, project tracking, and building software solutions.

Key features of VSTS (now Azure DevOps) included:

1. Version Control: Offered both Git and Team Foundation Version Control (TFVC) for source code management.
2. Agile Planning Tools: Supported agile methodologies with tools for backlog management, sprint planning, and Kanban boards.
3. Build and Release Services: Enabled Continuous Integration/Continuous Deployment (CI/CD) pipelines.
4. Testing Tools: Included tools for automated and manual testing.
5. Collaboration Features: Integrated with collaboration tools for team communication.

In September 2018, VSTS was transformed and rebranded as Azure DevOps, enhancing its capabilities with a broader set of developer services. Azure DevOps continues to offer a suite of tools that encompass the functionalities of VSTS but with additional features and integrations.