Anthro: Anthropomorphic animals. Bipedal characters, the most frequent type found on e621. Human traits such as hands and breasts are common, but even slightly anthropomorphic characters should be tagged as anthro.

Feral Non-anthropomorphic animals. Usually quadruped. Includes fictional and mythological creatures such as dragons. Can be tagged regardless of the level of intelligence displayed, as long as the physical form is almost completely feral.

Human Characters who appear to be entirely human, with no non-human traits such as pointy ears or wings. Because e621 is a furry board, human-only posts are rarely approved.

Humanoid Bipedal, usually mammalian-like beings that are neither fully human nor furries. This includes, amongst other, animal humanoid, aliens, human-like constructs such as androids and golems, and fictional species such as orcs and elves.

Taur Characters whose lower body is that of a multi-legged feral animal, and the upper body of an anthro, human, or humanoid. As they are not fully feral, taurs should not be tagged as feral.