Stellarators are “generators of stellar energy”, and their principle was developed before tokamaks. A helically twisted magnetic field, necessary for successful plasma confinement, is generated entirely by external magnetic coils of various shapes. The stellarator is a device capable of continuous operation, which is an important feature for a power plant. However, stellarators experienced a revival only recently, when sufficient computational power for creating the desired magnetic coil shapes became available. There are more than ten stellarators operating around the world. The largest include Wendelstein 7-X in Germany and the Large Helical Device in Japan.