Myelinated refers to nerve fibers that are covered with a protective sheath called myelin. This sheath is made of fatty substances and helps to insulate the nerve fibers, allowing electrical signals to travel more quickly and efficiently along the nerves. Myelination is crucial for the proper functioning of the nervous system. In the human body, myelinated fibers are primarily found in white matter of the brain and spinal cord. These fibers are essential for rapid communication between different parts of the nervous system, facilitating processes such as reflexes and coordination of movement. Myelination plays a key role in overall neural health and function.