It has you create budget categories that are essentially subaccounts of your bank accounts.
For example I allocate $200 per month for property taxes. The balance of that subaccount builds up over the course of six months until my property taxes are due. When the check clears I assign it to the property taxes category and it reduces the balance in the subaccount.
I know someone who does the same concept with actual bank accounts at ING. He has one account for vacation, one for car replacement, etc.