For danbooru purposes, a robot is an autonomous mechanical or electronic machine. This tag is essentially an "other" category for robots.
- Android - Robot that looks very like a human
- Clank - Steam-powered and/or clockwork robot
- Cyborg - Life that combines organic and robot parts
- Humanoid robot - Between robot and android
- Mecha - Giant robot
There is little consensus on which machines qualify as robots, but for tagging, use the following guidelines (in order of importance):
- Does not look like a human. If it has a head with a face and two arms, it's probably a humanoid_robot
- Acts independently with some degree of intelligence and awareness, else it's a machine
- Generally smaller than a car, else it's a mecha
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