Special Purpose tractors have evolved from the earliest days of tractor production. They started off with Farmers or the local Blacksmith, dealer or engineer, adapting a standard tractor to do a particular job better or for a task that a tractor was not suitable for. As the market for some types has grown manufactures have built there own or often bought them in and badged them in the quest to offer a full line up of models. The Line between being a special purpose tractor and a Self Propelled Machine is not clear cut.