User
A User is the user name used as the login value for several operating system job definition. Users must be defined in the database.
If you schedule a job on an agent, on a pool, or on a dynamic pool, the job runs with the user defined on the pool or dynamic pool. However, the User must exist on all workstations in the pool or dynamic pool where you plan to run the job.
Users can be defined in a specific folder if you want to organize them by line of business or some other custom category.