Kick start refers to a method of starting an internal combustion engine (usually that of a motorcycle) by pushing a ratcheting lever with one's foot. Kick start mechanisms were almost universally a part of motorcycle engines before the mid-1970s, and were phased out of production over the next five years or so as electric starters became standard equipment for engine starting. There were some motorcycles produced that had both a kick starter and an electric starter.
Many mopeds and scooters still carry both a kickstart and an electric start, the former being useful in case the latter fails, as scooter and moped batteries tend to be smaller and, as a result, run down much faster than other forms of automotive batteries. Also, it is usually not possible to push start a moped or scooter with automatic transmission.
Today, dedicated off-road motorcycles and many ATVs use kick start systems due to the increased weight of electric starters. The majority of the cheap two-wheelers in developing countries also utilize kick start levers.