The hardware clock can either be set to UTC or Local Time. UTC is "Coordinated Universal Time", basically it's GMT where all other timezones are offset from. Local Time is the time in your current timezone. To change the hardware clock to UTC or Local Time after installation, follow the steps below.
Note: in Kwheezy versions 1.0.1 and below, selecting local time in the installer does not take effect.
Login as root using the following command:
Enter the 'root' password when prompted.
Then the following command:
hwclock --systohc --localtime
hwclock --systohc --utc
Then logout the root account: