A mountain bicycle or mountain bike
(abbreviated MTB or ATB (All Terrain Bicycle)) is a bicycle designed for mountain biking , either on dirt trails or other unpaved environments. In contrast, road bicycles are not rugged enough for such terrain. Some mountain bikes are also fitted with bar ends on the handlebars, but with the increase in popularity of riser handlebars (as opposed to a flat straight handlebar) fewer riders use bar end extensions. In recent years, front wheel suspension has become the norm and full front and rear suspension is becoming increasingly common
. Mountain bikes have wide, knobby tires for extra traction and shock absorption.
