An object manager has all administrative rights for editing objects. Object managers have access to all objects of their location as well as all projects contained therein without being explicitly assigned.
This role is the default role when creating new users. A user can work on his own or assigned projects, i.e. create projects, edit projects (if the user in the project has the role Project owner or Coworker), read projects (if the user in the project has at least the role Reader).