Membership types define each type of membership with its duration, costs, restrictions and associate membership options. Set up membership types by clicking on Membership types from the Setup panel.
You cannot delete any membership type for which there are one or more memberships.
Changing a membership type's duration, cost, restrictions and other values other than description does not change any memberships which have already been created. But changing the description of the membership type does affect those already-created memberships.