Car Segmentation by Society of Indian Automobile Manufacturers

Car segments as per SIAM (Society of Indian Automobile Manufacturers)
The classification of segment is done on the basis of the length of the vehicle (Passenger car segment)
A1 Segment - Mini - Up to 3400mm (M800, Nano)
A2 Segment - Compact - 3401 to 4000mm (Alto, wagon r, Zen,i10,A-star,Swift,i20,palio,indica etc)
A3 Segment - Midsize - 4001 to 4500mm (City, Sx4, Dzire, Logan, Accent, Fiesta, Verna etc)
A4 Segment - Executive - 4501 to 4700mm (Corolla, civic, C class, Optra, Octavia etc)
A5 Segment - Premiun - 4701 to 5000mm (Camry, E class, Accord, Sonata, Laura, Superb etc)
A6 Segment - Luxury - Above 5000mm (Mercedes S class, 5 series etc)
B1 Segment - Van - Omni, Versa, Magic etc
B2 Segment - MUV/MPV - Innova, Tavera, Sumo etc
SUV Segment - CRV, Vitara etc

Classification of Cars based on body Shape
ONE BOX (VAN/MPV) - It means Engine area, Passenger area & luggage area all in one box. There wont be separate compartment. For eg. Omni, Ace Magic, Versa
TWO BOX (HATCHBACK) - It means Engine are has a separate cabin while Passenger area and luggage area are together. For eg. M800, Alto, Santro, i10, A*, Swift etc.
THREE BOX (SEDAN/SALOON/NOTCHBACK) - It means Engine area, Passenger area & luggage area all are having different cabin. For eg. SX4, City, Fiesta, Dzire, Ambassador, Indigo CS etc.
ESTATE/STATION WAGON - Its nothing but sedan whose roof is extended till the rearto create more boot space. For eg. Indigo Marina, Octavia Combi, etc.
SUV (Sports Utility Vehicle) - These vehicles have large tyres, higher seating, higher ground clearance. The engine area is separate, but the passenger & luggage area are enclosed together. Most of these vehicles are equipped with either 4 wheel drive system or has the option for that. For eg. CRV, SAFARI, GRAND VITARA, PAJERO etc
SEMI NOTCHBACK - Its a sedan whose boot door can be opened like a hatchback (wagon r, swift), where the rear wind sheild too opens along with the boot door. Unlike sedan whose rear wind sheild is always fixed. There are only few examples for SEMI NOTCHBACK - Skoda Octavia, Accent Viva.