The main entities of the data structure in Dynamics 365 Human Resources are job, positions and workers.
A job is a collection of tasks and responsibilities.
A position is an individual instance of a job.
You can have several positions connected to one job.
You can not have more then one job connected to one position
You must always have a position connected to a job.
A worker is a person in the system.
A worker can have two positions up to a full-time position
But a position can’t be filled by two (or more) workers (no, it can’t be done, I’m sorry).
The job is CRM consultant, the position is CRM consultant in Oslo which is assigned to me.
You can’t create a position before you have created the job. A worker can be connected to one ore more positions, but they can’t be connected directly to a job. Only the position is organized in the standard hierarchy.