Axons are long, slender projections of nerve cells, or neurons, that transmit electrical impulses away from the cell body. They play a crucial role in the nervous system by connecting different parts of the body and facilitating communication between neurons. Each axon can branch out to form connections with multiple target cells, allowing for complex signaling. The surface of an axon is often covered with a fatty layer called myelin, which acts as insulation and speeds up the transmission of signals. Axons can vary in length, with some extending just a few millimeters while others can be over a meter long, such as those found in the spinal cord.