Terminology in Alma
Fulfilment. Fulfilment is a category of functions within Alma that include circulation of stock and dealing with patrons. Anything that fulfils a request - from a patron or for a library process - comes under Fulfillment.
Circulation Desks are work location(s) in the library that handle patron fulfillment. You would set this as your Location in the Alma menu (upper right corner) so that materials are checked out and in properly.
Fulfillment Units are shelving locations with similar lending/return policies and blocks.
Institution is the campus that contains a library or libraries.
Library is each individual library in a campus.