A role is given to every player of the ambush games at the start. To win the players have to use their roles correctly.
Roles are divided in two parts: Team roles and game roles
This part of the role decides what team you're on. For example the Spy healer is on the spy team. This is usually a part of the roles name or sometimes mentioned by the host.
This part of the role decides what night actions you have. For example the portector can protect people. This is usually explained by the host.