Quotes.  1 That's my child! My property! (To Angharad)  2 Do not, my friends, become addicted to water, or it will take hold of you and you will resent its absence!.  3 Mediocre!.  4 Return my treasures to me, and I myself will carry you through the gates of Valhalla. You shall ride eternal. Shiny, and chrome. (To Nux)
While most U.S. Passport numbers are nine digits and most U.S. visa numbers are eight digits, some are not. Last year, we implemented a workaround for entering document numbers that do not fit the usual pattern. That workaround is no longer necessary as we have implemented a permanent fix as part of our June 2011 upgrades.
I'm not sure if you're asking what the card number is on a Visa debit card, or if it is different than a Visa credit card... so I will try to answer both. A Visa card # is a 16-digit number, that uses a specific format. In order to be a valid number, the 16 digits have to work within the Mod 10 algorithm. All Visa numbers start with a 4. MasterCard numbers start with a 5, Amex is 3, and then there are a few others, including Discover card, etc.