A double-decker bus or double-deck bus is a bus that has two storeys or decks. Double-deckers are primarily for commuter transport, but open-top models are used as sight-seeing buses for tourists, and there are coaches too for long-distance travel. They appear in many places around the world but are presently most commonly used as mass transport in cities of Britain, in Ireland, in Hong Kong, Berlin and in Singapore.[1][2]
The earliest double-decker horse-drawn omnibus appeared in Paris in 1853 and such vehicles were motorised in the 1900s.[3] Double-decker buses were popularised in Great Britain at the start of the 20th century[4] and today the best-known example is the red London bus, namely the AEC Routemaster.[5] Double-deckers in urban transport were also in common use in other places, such as major cities of India[6], but were mostly diminished or phased out by the end of the 20th century. However it has been maintained and remains common in Britain as well as Ireland and Hong Kong, while in Singapore and Dhaka they have been introduced and expanded into large numbers after British colonial rule.