There are 2 Categories of permits, and each category has a permit type.
Your permit category will either be a fixed permit or a transferable permit.
This is a parking permit that is linked to a specific vehicle and it's registration number. It cannot be used for any other vehicle.
This is a permit that is transferable between vehicles.
The permit also has a type A or B. The type of permit you may be eligible for will depend on the parking restrictions adjacent to your street.
Type A - Resident only parking exemption permit
This permit allows the vehicle specified on the permit to park in the Resident Only Permit zone, or overstay the time limit zones. It is only valid for the street listed on the permit itself.
Type B - Time limit parking exemption permit
This permit allows a specified vehicle to overstay the time limit in a time restricted parking area indicated by parking control signs. It is only valid for the street listed on the permit itself. It cannot be used to park in a Resident parking only permit zone.