Queues: Group of users who can owns the records .
Case teams:we create case team role and can assign this to predefined case team.
But I had a lot of confusion about case teams.
Can any one give example please?
A case team is simply a group of individuals working on a case; there are multiple people involved in the resolution of the case. For example, a case might need a service tech to take care of the hardware and an IT person to take care of the software, so both people need access to the case, with the case owner (perhaps a customer service representative) acting as liaison between the customer and the two people actually handling the case.
A case queue is a holding area where cases not yet assigned reside until someone accepts the case. Nobody has yet started working on the case, so anyone in the queue (people skilled to handle a particular set of problems) can accept the case and begin working on it. When a case is in a queue, nobody owns the case. Typically, a case that has a case team already has resources assigned to the case to resolve the issue, while a case in a queue has not yet been given any attention to. Of course, this may vary based on an organization's support structure, but this is a pretty typical representation.
Queue: The group of people who can take the ownership of the case and work on the case. Case can be assigned to a user or queue. In sharing settings, if Case object is defined as Public Read/Write/Transfer then queue is not needed.
Queue members can be of following:
Case Team - Case teams help groups of people work together to solve a case, such as a support agent, support manager, and a product manager.
Case team member may or may not directly take the ownership of case, but plays a specific role and provide guidance or valuable inputs for case closure. He can be Technical specialist, Domain expert or can be the Customer.
Case Team members can be User or Contact and will have team roles and access rights as Private, Read Only or Read Write
From data visibility point of view this will help you to understand: