Can someone explain how are departments, teams and customer groups interrelated

[iitbmanish]

I created users and agents.
users i mapped to customer groups
agents i mapped to teams

Department i used for mapping of the team to customer groups.
so user 1 can be mapped to customer group a,b,c

agent 1 can be mapped to team 1
agent 2 mapped to team 2
agent 3 mapped to team 3

and department contains the following
customer group a - team 1
customer group b - team 2
customer group c - team 3.

so now if user 1 creates a ticket in customer group a, only agent 1 will be able to see the ticket. similar for customer group b and c.

is there any other way of doing these mappings.