This is the 156th most frequent German word.
man
"Man" = One, people, someone, or they (used for general statements).
In this context, 'man' refers to an unspecified group or the general public, conveying hearsay or common knowledge.
Man sagt, dass es morgen regnen wird.
They say it will rain tomorrow.
Here, 'man' is used formally to indicate a general prohibition applicable to anyone in the specific context.
Man darf hier nicht rauchen.
One is not allowed to smoke here.
The word 'man' is used impersonally here to mean 'one' or 'people in general', expressing a general statement about politeness.