Still, you can close a given circuit and trigger Tor to create a new one using the [[New Circuit for this Site|doc/anonymous_internet/Tor_Browser]] button of *Tor Browser* or the [[*Onion Circuits*|doc/anonymous_internet/tor/circuits]] utility.
The computer clock is fixed a first time, approximately, before connecting to Tor, either [[automatically|doc/anonymous_internet/tor#automatic]] or [[manually|doc/anonymous_internet/tor/troubleshoot#clock]].
The computer clock is fixed a second time, precisely, to prevent a website from identifying you by analyzing minor differences of your computer clock with the correct time.