Use case for functions exposed by wasp/server/operations

When you define an operation in

main.wasp

main.wasp

, the framework compiles and creates 2 exports of the same name. One from

wasp/client/operations

wasp/client/operations

and one from

wasp/server/operations

wasp/server/operations

. Of couse you would invoke the operation from

wasp/client/operations

wasp/client/operations

to on the frontend. I'm wondering: what is the use case for the function exported from

wasp/server/operations

wasp/server/operations