A single-decker bus or single-deck bus, is a bus that has a single deck for passengers. Normally the use of the term single-decker refers to a standard two-axled rigid bus, in direct contrast to the use of the term double-decker bus, which is essentially a bus with two passenger decks and a staircase. These types of single-deckers may feature one or more doors, and varying internal combustion engine positions. The majority of single-deckers have a length of up to 12Â m (39Â ft 4Â in), although some exceptions of longer buses exist. They also typically weigh between 11 and 14Â t (12 and 15 short tons).
In regions where double-deckers are not common, the term single-decker may lack common usage, as in one sense, all other main types of bus have a single deck. Also, the term may become synonymous with the name transit bus or related terms, which can correctly be applied to double-deckers too.