Choppers: Highly customized motorcycles based on a cruiser-style frame with long rake (longer front forks). They are also usually bare of various accessories and other non-essential parts. Many are created more for show than rideability.

Cruisers: A range of small to large motorcycles designed for comfort and looks with a relaxed upright or reclined seating position. They often use lots of chrome and may be highly customized.

Sports bike: Performance bikes that are usually lighter and smaller in structure than the cruiser. These motorcycles are racing bikes and have four-cylinder engines ranging 600cc to 750cc. “Super bikes” can also provide up to 1,000cc are included in this category.

Touring bike: These motorcycles offer large displacement parts, to protect from inclement weather and heavy winds; high-torque engines; comfortable, upright seating positions; and large capacity fuel tanks for long-range mileage.

Sports – Touring bike – these motorcycles are designed to blend performance of a sports bike with long-distance capabilities of a Touring bike – performance while providing comfort and relative safety to the rider. Sport touring has evolved over decades from simply strapping a bag to the back of any sporty motorcycle to a very specified genre of motorcycle riding for which specific models of motorcycles, luggage, riding apparel and other accessories have been designed.

Standard/Street bikes: Standard bikes have a riding position midway between the forward position of a sports bike and the reclined position of a cruiser. Luggage capabilities are often an optional extra. Standard bikes are popular for commuting and other city riding because the upright riding position gives greater visibility in heavy traffic (both for the rider and to other road users) and are more comfortable than the hunched over sport bikes. Naked bikes are included in this category.

Off-road bikes: These include dirt bikes and are built for rougher terrain. They have larger, deeper-treaded tires, small engine, long suspension travel and high ground clearance, and no street accessories.

Dual-Sport: these are “on-off road” bikes. Sports Touring bikes adapted for off-road driving.

Enduro – these are off-road bikes adapted for legally driving on the streets.

Mini bikes: Very small bikes designed to be simple run-around fun for both children and adults. Generally they have no hand-operated clutch or gearbox to simplify operation. Also known as Mini Motos. Not street-legal in most countries and jurisdictions. May be used for racing by all age levels.

Sidecars: A sidecar is a one-wheeled device attached to the side of a motorcycle, producing a three-wheeled vehicle. A sidecar motorcycle is different from Trike – with the sidewheel not directly aligned with the rear motorcycle wheel, and is usually powered by the rear wheel only.

Trikes: Motorcycle with three wheels. A motorized tricycle’s wheels may be arranged in either configuration: delta or tadpole. A delta trike has one wheel in front and two in back, and the tadpole trike has two wheels in front and one in back.
A common arrangement is to fit chopper-style (“ape hanger”) front forks to a VW Beetle engine and transaxle, popular because it is largely self-contained on a single subframe. Similarly, the engine, transmission and rear wheel may be taken from a large motorcycle as a single unit, and used in the construction of a tadpole trike.

Scooter: Motor Scooters are short-distance motorcycles with small wheels (357 mm or 14 in. in diameter) and engines in the swing arm. Typically, these run less than 125cc, but some larger scooters exceed 250cc. One popular scooter is the Honda Lead 80.

Mopeds: Small, light, inexpensive, efficient rides for getting around town. Usually started by pedalling (motorcycle + pedals = moped). Mopeds typically have an engine mounted to the frame with a chain supplying the drive force to the wheel.

Credit for images to respective owners at Wikimedia under GNU Free Documentation License.