The bow drill is a traditional fire-starting tool that uses friction to ignite tinder. It consists of a flexible bow, a spindle, a fireboard, and a socket. The bow is used to rotate the spindle against the fireboard, creating heat through friction. When the temperature rises enough, it produces an ember that can be transferred to tinder to start a fire. This method is one of the oldest known techniques for fire-making and is often used in survival situations. The bow drill requires practice and skill to master, making it a popular subject in wilderness survival training and outdoor education programs.