Why is a prisoner someone who is in prison but a jailer isn’t someone who is in jail?

Technically both are in jail. The jailer is more of the guard than the actual inmate that has committed a crime but, some people see them as criminals to because they are the one locking them up from the public due to their actions. Most punishments now a days are being looked at as to strict or harsh.

jailers put people in jail or jail them

Explanation:

prisoner is just a name given to  someone to describe what they are , the same is with jailers they jail people or watch people in jail this describes what they do and what they are .

               I've never thought of it that way unique question .

sorry answered wrong answer