Single Personal use:
My suggestion will to use any local server installation on your PC / Laptop, and then have regular backup to any external drive or drive cloud service. My recommendation will be the free edition of Visual SVN Server.
Academic groups:
If you don't have an issue that your source code will be shared worldwide, pick from below listing:
If you want to have closed source between your group members check below case for start-ups.
Start-ups / entrepreneurs:
With limited budget, unlimited number of users, project management features, collaboration, issue tracking, redundant backups, pick from below listing:
Commercial companies:
If you have reasonable budget, looking for complete SDLC (Software Development Life Cycle Management) / ADLM (Application Development Life Cycle Management), complete collaboration between distributed teams, trusted company by major customer references with lots of plugins / marketplace you may expand at anytime based on your needs. Atlassian will be the best for you; this can range from small to large enterprise.You will need the following products as start:
- Confluence: For team collaboration.
- Bitbucket: Git & hosting.
- JIRA: Planning, assignment tracking, issue tracking.
You can find Gartner report shared here. Customer references shared here (List includes: Nasa, Twitter, Facebook, BMW, Audi, Cisco, Adobe, ...).
Hope this helps someone there.