A b-train is a big truck that can carry a lot of things. It's made up of two different parts that are connected together. The bigger part in the front is the truck with its own wheels, and the smaller part in the back is also a truck with its own wheels. Both these parts are connected together by a special hitch that lets them move together as one unit. This way, the b-train can carry more things than a regular truck.
It's kind of like a train toy that we play with. They have different train cars that can be connected together to make a longer train. The b-train also connects two truck parts together to create a bigger truck that can carry more things.
B-trains are used by companies to transport goods like food, cars, and other supplies over long distances. They are often seen on highways and freeways because they can travel faster and carry more things than regular trucks.