There are various kinds of golems; however there are two main categories.
Arcane golems are the ones that are typically spoken of in legend. These golems include the ones made from clay and stone, but also include iron.
Necromantic golems are associated with bone, blood or flesh. Golems of this nature have only been created for the last few centuries.
Golems can take on a variety of shapes and sizes, but are usually constrained by the material that they consist of.
Clay and stone golems are more formless. They just barely appear to be humanoid, and may not have expressive features. Their bodies can also be more misshapen and asymmetrical.
Iron golems can be formless, but are more often shaped to look like armor. In fact, expert practitioners of the arcane arts will typically animate an entire suit of armor to act as a golem for them.
Necromantic golems are shaped by the type of bone and flesh, but they can also be modified by the will of the caster. Blood golems are perhaps the most peculiar variety, since it can be so easily molded in a quick manner.
Clothing and Adornment
Though they can, in theory, be clothed, golems do not suffer pain or shame. It is considered a waste of time to offer garments to the creatures, although some wizards have been known to adorn their golems with straps or belts, effectively making them a beast of burden in addition to a protector. Many golems also have markings carved into them for personality as well. These can be quite tribal, or they can have an enchanted aura.
Temperament and Behavior
Golems have no emotions. They live to serve the request of their caster, and as such, will not cease their task unless they have been destroyed, or their caster has met their end.
Technically, golems do not die unless they are disenchanted by their caster. Even if you broke them into pieces, they would still exist. If a wizard was able to piece them back together, the golem would function once more. If it wasn’t put back together it would remain permanently paralyzed.
There are legends of living golems that have become self aware. Some of the tales say that their master gave them their freedom, while others say they fought their wizards as if they were slavers.