Threads are one of a bolt’s main characteristics. A thread functions under the basic concept of an inclined plane that is spiraled around the length of a fastener. This spiral requires rotational pressure to be inserted into a slot. Turning the bolt causes the threads to move the complementary slot or nut upward against the inclined plane. The greater the torque, or turning force, the greater the pressure pulling the nut forward along the threads. This in turn creates tension in the bolt and a clamping force that presses the two component together. A higher number or a denser arrangement of threads can strengthen the joint. In addition, cutting threads into the bolt after it has been heat-treated  improves thread strength.