If you have money in your checking account, you can write a check to another bank account. Even if the accounts are in different banks, that's fine: Your bank will accept your check as readily as anyone else's. But if you write a check without the money to cover it, that's another story.

Check Kiting

Check kiting exploits the time lag created when the bank processes your check. For example, if you get paid tomorrow but you need cash today, you write a check from Bank A to Bank B. You withdraw the money you need, then deposit your paycheck tomorrow before the check clears Bank A. Professional kiters write checks back and forth between two or more banks for large sums. If nobody detects it, this amounts to an unauthorized loan from the banks for weeks.