The jugular veins are major blood vessels located in the neck that carry deoxygenated blood from the head and neck back to the heart. There are two main types: the internal jugular vein, which drains blood from the brain and face, and the external jugular vein, which drains blood from the outer structures of the head and neck. These veins play a crucial role in the circulatory system by ensuring that blood is efficiently returned to the heart for reoxygenation. They are often used in medical procedures, such as central venous catheterization, due to their accessibility and size.