This will probably work for Ubuntu and related distros.

If your time is off on your server or other Linux computer and you want to get your server's time set correctly and have it stay correct, then you would probably like NTP.

NTP stands for Network Time Protocol and it's a way of keeping your computer system's time correct by syncing your computer's time with those of servers on the internet that maintain the correct time.

From a command line, you can type date -R to get your systems time.

When I type it, I get this: Wed, 28 Jan 2015 18:50:17 -1000 and that is not correct.

Since my system's time is not correct, and I want to change that, I can install the ntp package.

I can install the ntp package by running the command apt-get install ntp while having root privileges. 

Once installed, it may take a minute or so for your computer's time to sync with an NTP server.

You might also find out that your system's timezone is incorrect. If that is the case, then find out how to change the timezone on your Debian server or computer.