Bike

Road bicycles are designed to be ridden fast on smooth pavement. They have smooth, skinny tires and "drop" handlebars, and can be used for on-road racing. They are usually lighter than other types of bicycles. They can be ridden on paved trails, but most people find them uncomfortable and unstable on unpaved trails. Most road bikes are not capable of carrying heavy loads, so are not very suitable for commuting or touring.

Cyclocross bicycles are a special type of road bike designed to be raced on a mixed surface course (combination of pavement, unpaved trails, gravel, grass). They have a drop handlebar like regular road bikes, but the tires are a littler wider for more off-road traction, and they have a different style of brake that helps to prevent mud buildup in the frame.

Touring bicycles are another special type of road bike. They are designed to be ridden on pavement, but are more durable for use on self-supported long-distance riding. They have all of the necessary mounting bolts for cargo racks and fenders, and although they still have a drop handlebar, they usually have a more relaxed frame design so that the rider is more upright, for more comfort when riding long distances for multiple days at a time. They have a lower gear range compared to regular road bikes, to allow for carrying heavy loads up steep hills. They also make good commuter bicycles, because of their durability and ability to carry heavy loads.

Adventure Road Bicycles are one of the newest categories of bicycle. They are sometimes called all-road bikes, any-road bikes, or gravel bikes, and are the most versatile sub-category of road bike. Similar to cyclocross bikes, they have drop handlebars and the ability to use wider tires. The frame geometry is longer and more upright compared to a cyclocross bike, however, making these bikes more suitable for long days in the saddle, light touring, and commuting.

Triathlon/Time Trial Bicycles are road bikes with a special design that maximizes their aerodynamic properties. The handlebars are also a special aerodynamic design that allows you to crouch forward while riding, to minimize the wind resistance against your body. Triathlon/time trial races usually have staggered starts, where each racer starts on his/her own; these bicycles are usually not allowed to be used in mass-start races.

Fitness Bicycles have most of the advantages of regular road bikes--lightweight frames and relatively narrow tires for efficiency on pavement--with a flat or upright handlebar. These bikes are designed for people who want a light, high-performance bike, but don't like the drop-handlebar riding position of a regular road bike. These bicycles are sometimes called flat-bar road bikes or performance hybrid bikes. Most of them can accept somewhat wider tires, to make them suitable for use on unpaved trails. They usually have the ability to mount cargo racks and fenders, which make them good commuter bikes.

Track/Fixed-Gear Bicycles or fixies are designed to be ridden on a velodrome, which is a banked oval track specifically for bicycle racing. Some commuters prefer track bikes, however, due to their simple design, which makes them easy to maintain. They have a single gear that does not provide the ability to coast, so if the bike is moving, your feet must be pedaling. For even more simplicity, some riders prefer to not have brakes, since the fixed-gear mechanism can act as a brake. Most track bikes have drop handlebars, but some riders outfit theirs with flat or upright handlebars.

Mountain Bicycles are design for riding rough off-road trails. They have flat or upright handlebars, and a very low gear range for pedaling up steep trails. Most mountain bikes have some type of shock absorbers or suspension. Mountain bikes with front suspension only are called hardtails; mountain bikes with both front and rear suspension are called full-suspension bikes or duallies. Mountain bikes with no suspension are called rigid. Mountain bikes can be outfitted for use as touring or commuting bikes, although they would not be as light or efficient as traditional touring or commuting bikes. Fat bikes, with their extremely wide tires, are included in the mountain bike category.

Hybrid Bicycles were originally conceived to provide the advantages of both road bikes and mountain bikes. Their large, padded seats and upright handlebars provide a comfortable riding position, and are best for casual riding around the neighborhood or bike paths, short-distance commuting, and errands around town. They can be ridden on paved roads, but are not as lightweight or efficient as road bikes. They are ideal for paved or unpaved bike trails, but are not appropriate for rough off-road mountain bike trails. The tires are usually a medium-width with a semi-smooth tread, to provide a fairly smooth ride on pavement, but enough grip and cushion on unpaved trails. Most hybrid bikes have front suspension to smooth out small bumps, but some are fully rigid.

Dual-Sport Bicycles are a sub-category of hybrid bikes oriented towards riders who want the multi-surface versatility of a hybrid bike, but want a little more aggressive style and riding position. They have a flat or upright handlebar, although not as upright as regular hybrid bikes; they usually have a smaller, more performance-oriented seat, rather than a large comfort seat. Most have front suspension. Dual-sport bikes make good commuter bikes, and are also good for touring on unpaved trails.