Boats
tiller is a
lever attached to a rudder post (american terminology) or rudder stock (english terminology) in order to provide the
leverage for the helmsman to turn the rudder. The tiller is normally used by the helmsman directly pulling or pushing it, but it may also be moved remotely using tiller lines .
As the size of boat increases the power needed to control the rudder via a tiller becomes excessive. In the 21st century, tiller steering tends not to be used on new boats with an overall length in excess of approximately 10 metres.
Cars
Tillers were also present on some very early cars, as with a boat, performing a steering function. Eventually, the steering wheel became the only car steering utility.
Agriculture
The term tiller can also refer to a garden implement used for turning soil (or the person who operates such a device). The purposes of this activity is to aerate , control weeds, and conserve moisture in the ground.