Tarantulas comprise a group of large and often hairy spiders belonging to the family Theraphosidae. There are currently about 1000 species that have been identified. The term tarantula is usually used to describe members of the family Theraphosidae, although many other members of the same infraorder (Mygalomorphae) are commonly referred to as "tarantulas" or "false tarantulas". Some of the more common species have become popular in the exotic pet trade. Wikipedia