Configuring Time Off Manager

Hi,

I have installed TOM, and the approval processes all seem to be working perfectly.
I dont know what the function of the 'Pay Cycle' or 'payroll System' is or what they are used for.
I assume the Time Off Balances accrue automatically, but dont know what rate this is at, or how this information is provided.

Is anybody able to help me with these queries?

Thanks, Jarvis