Is os.time only gets the client?

Hello developers!
Im trying to make a chat like discord like this. But i am confused on real time
And i am using :FireServer() to send the message. does it only gets the real time of the client who fires it? Or it changes it to a different time of the client?

ā€¢ if the player fires the event, it will only get its real time on who fires it.

I am trying to make:

os.time() works on client and server