If you have limited knowledge about troll creatures then you will be surprised to know that there are three general categories as to which where they do belong. The most popular category are the "Giant Trolls" due to the film "Troll Hunter" which featured some of the interesting creatures. Surprisingly, the other categories are the "Human-Sized Trolls" and the "Dwarf Trolls".
Giant trolls are monsters with huge sizes that either live in the deep forest or in the mountains. Their characteristics are very similar to wild beasts where most of them hunt other animals for food. I suggest that you should watch the Troll Hunter movie to know more about them.
Human-sized trolls dwells in the deep enchanted forest. They are actually mystical creatures that possess diabolical powers in which they often use to trick humans. Most sources claims that they have the ability to shape-shift into various forms such as a pretty women, animal and even objects.
Dwarf trolls are the complete opposite of the giant trolls. Again, according to most sources, these small creatures are quite smart and talented with various skills. As for their dwelling place, they live deep underground places.