Various Nix teams exist to work together. Teams generally have certain authority, responsibility and accountability over their resources. There are currently no strict requirements from teams.
As a team you might want to have a new GitHub team, Matrix room or permissions to a repository. Adding a team as shown below does not automatically give you that. Instead see the resources page.
The most official teams are the ones declared in the teams section on the homepage.
To add a new team to this list, open a PR on the nixos-homepage repository.
More Nixpkgs-specific teams are declared in the maintainers/team-list.nix file, which can be programmatically accessed using lib.teams.
To add a new team to this list, open a PR to change it.