system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: the difference between general anaesthesia, a medically indjced coma, and a coma caused by a traumatic brain injury, aside from the fact that doctors induce the first two and can easily reverse them. Is there anything different going on in your body/mind while in these States?
gpt
The difference between and induced coma and general anesthesia is time and reason. General anasthesia is short and used to provide safety and comfort during surgery, where an induced coma is longer and used to slow the metabolism of the brain for an extended time to prevent excessive swelling that can cause more permanent damage. 

A coma from injury occurss when certain parts of the brain are damaged. A person may come out of a coma if those parts can be healed, but they may still have permanent damages that last after they wake up.