Topic summary

Road bike

Extracted from the Wikipedia article Road bicycle.

The tires are narrow, high-pressure, and smooth to decrease rolling resistance
The handlebars are bent ("dropped") to allow the rider position to be leaned forward and downward, which reduces the forward vertical cross-sectional area and thus highly reduces the air resistance
They usually use derailleur gears; however, single-speed and fixed-gear varieties exist (which often are used city-wide, due to simple maintenance from their simple designs).
They either use disc brakes or rim brakes (although there might be technical differences, for example, road bike calliper brakes use shorter and wider pads than mountain bike cantilevers)
The bicycle is of lightweight construction using materials such as aluminium alloys or carbon fibre.
They usually use clipless pedals and special shoes in contrast to flat pedals, usually installed on mountain bikes.