Other types are carbon film which is a thin layer of carbon on a ceramic rod, and metal oxide and metal glaze on glass rods. Wire wound resistors are used where the resistor has to dissipate a lot of heat. Faulty resistors have gone open circuit or changed in value. They never go short circuit. Some resistors are designed to change in value when heated.
Some resistors change in value when exposed to light.
Most resistors are colour coded to indicate their value and tolerance. Wire wound resistors have their value written on them. Resistors generate heat. Resistors have a wattage rating. The higher this rating the more heat they can dissipate.