The vast majority of the configuration for the TD suite happens through giving a user administrator (TDAdmin) access to the tool. Some reasons you would give a user access to admin is to add/edit ticket types, project types, users, client portal styling, services, service categories, ticket workflows, project workflows, desktop templates, attributes for the various components, request forms, etc. For operational tasks such as working on/managing tickets and projects, a user would not need admin access. I believe that you already know all of this information as I have laid it out, so can I ask what about the pain point(s) you are experiencing that drove you to ask this question? I wonder if the motive for asking is deeper than just wanting to know what is found within admin.
Are you really looking for more siloed permissions surrounding the administration console? If so, we hear you and are working towards this effort. A big push surrounding this effort is the the ability to make a user an admin over a specific ticketing application, vs having to make them an admin over the entire environement. If that, and any other 9.2 features interest you, I will link you to the release notes for your convenience. https://community.teamdynamix.com/releases/17/version-9-2#ability-to-create-admins-for-specific-ticketing-applications
Please let me know how else I can help assist.