How are groups, teams, departments and divisions classified?

Processes are structured sets of activities designed to accomplish a specific objective; they describe workflow, not organizational units.

ITIL defines functions as units of an organization - such as groups, teams, departments, or divisions - that are specialized to perform certain types of work and are responsible for specific outcomes. Functions provide structure and stability within an organization and own the resources and capabilities required to perform their work.

Roles define responsibilities and authorities assigned to a person or team, but they are not the classification for organizational units like departments or divisions.

Technicians is not a formal ITIL classification and does not describe the organizational groupings referenced in the question.