Hi @auzty, the documentation on creating teams can be found here.
Quick summary is that "teams" are a collection of members that have conversations organized into "channels", which can be viewable to all members in the team, or private to a select number of people in the team.
You can have multiple teams on your system with the same "Team Name" (since it is just a display name), but the "Team URL" must be different for all the different teams on your system. I will submit a pull request to make this more clear in the documentation, thanks for bringing this up!