An execution queue is a "processor" of jobs; it controls how job instances run. In order to run, every job instance is assigned to a target execution queue. The queue controls how many job instances (of all the jobs assigned to the queue) can be running at any one time and the delay between runs. By default, the queue settings are local to the job, but you can also define queues as standalone objects shared by multiple jobs. When multiple jobs are assigned to the same execution queue, they will share that queue for executing.
Queues benefit from the same security access mechanism as other FlowForce Server configuration objects. Namely, a user must have the "Define execution queues" privilege in order to create queues, see also How Privileges Work. In addition, users can view queues, or assign jobs to queues, only if they have appropriate container permissions (not the same as privileges), see also How Permissions Work. By default, any authenticated user gets the "Queue - Use" permission, which means they can assign jobs to queues. To restrict access to queues, navigate to the container where the queue is defined, and change the permission of the container to "Queue - No access" for the role authenticated. Next, assign the permission "Queue - Use" to any specific roles or users that you need. For more information, see Restricting Access to the /public Container.