Endorsements on a Driver's License
Certain types of vehicles require an "endorsement", or special license, in addition to a Connecticut Driver's License.  Additional testing may be required to obtain an endorsement.  Some endorsements require a Commercial Driver's License and background checks.
Here is a list of endorsements issued by the Connecticut Department of Motor Vehicles:
A endorsement = Activity Vehicle
H endorsement = Hazardous Material
M endorsement = Motorcycle
N endorsement = Liquid Bulk/Tank Cargo
P endorsement = Passenger/Transportation
Q endorsement = Fire Apparatus
S endorsement = School Bus