[J_Darnley]

Not the parent, but...

You write a cheque to X. X hands it to their bank A. A asks your bank B for the amount on the cheque. B asks A for the cheque to check its valid. B sends money to A. Done. Which is why I thought they take days to be processed.

[ams6110]

Used to work that way. Not anymore. Routing number and account and amount are sent electronically to a check clearinghouse and the money is transferred sometimes the same day or even close to real-time. The paper itself gets scanned, and the original shredded.

See http://en.wikipedia.org/wiki/Check_21_Act