The Microsoft Team Foundation Server (TFS) has been around for some time, and, since its inception, it has used the Team Foundation Version Control (TFVC). Visual Studio Team Services have been added to provide a cloud service (much like, for example, GitHub, GitLab, or Bitbucket).

Nowadays, TFS and VSTS not only provide TFVC as a source control system, but can also use Git, which is the more popular choice:

TFS and VSTS still remain a great choice, when you are leveraging the work tracking abilities they offers. You can plan your work on a Kanban board (for example, assign tasks to developers, create user stories, and so on). However, it might be too oversized for a PowerShell developer. If your company already uses it, why not make use of it, create a team project with Git, and start coding?