A Call Center Queue or a Queue is a destination for any type of inbound calls. 
Inbound calls go through Queues before going to agents.

In the Call Center Queue Skills tab, you can prioritize your agents to make sure some of them pick up more often than others. This is useful if you wish to ease new agents into the dialer.

From the Dashboard, click on Call Center and select  Call Center Queues from the drop down.

In the Show Queues Section, click on the Action Button and select Settings from the drop down.

Go to the Skills Tab and configure the agent's priority for the Queue

To Assign User priorities the admin should select the Skill for each Users. The higher the skill, the higher the priority they have in the queue.  What this means is that if you give a user a 9 and a user a 1, the user with the level of 9 will take significantly more calls than the user with a level of 1. 

If both Agents have the same Skill Number, the call will be routed to agent with higher Weight

Click on Apply changes to save changes.

NOTE: You need to set Call Routing to Agent Queue Skills in order for the Skills to work under the Queue settings.