Semi-trailer trucks, or semi-trucks for short, are large transportation trucks that haul goods via a trailer attached to the back. The semi-truck is equipped with two or three axles which are made for hauling heavy cargo. Behind the main cabin is where the hitch is located, which can be used to attach to trailers, other trucks, etc. The cost to own a semi-truck could run up to $100,000 and maintenance would be upwards to $60,000. To drive a semi-truck, you’ll need a special license called Class A Commercial License.