Golems are magically powered constructs, often used for hard labor in more advanced polities.
Golems are first put together with various materials, typically cheap or scrap metal. Then, they are enchanted with animate spells. The more elaborate the golem's job, the better the spell and material used.
Golems are used for hard labor and for dangerous tasks that don't require too much intelligence. They are most often used for mining, as there is no need for any sort of cleverness when mining, and golem's can get down further into the planet than most people.