Coils are loops or spirals of material, often made from metal or wire. They can be found in various applications, such as in springs, where they store mechanical energy, or in electromagnets, where they create magnetic fields when electricity flows through them. Coils can vary in size and shape, depending on their intended use. In electronics, coils are essential components in devices like transformers and inductors. They help manage electrical currents and voltages by storing energy in a magnetic field. The design and number of turns in a coil can significantly affect its performance in these applications.