When you look at the front of your credit card, you might just see a string of numbers that is your account number. However, those numbers, along with some others on the back of the card contain a lot more information than just functioning as your personal account number.

"There are various purposes for all the numbers," says Ken Paterson, vice president of research operations and director, credit advisory service at Mercator Advisory Group. "All of these numbers make up your account number."

Paterson says there's "a lot of intelligence embedded in the first six digits." These numbers make up what's called the IIN, or Issuer ID Number and contain a lot of information including the card network on which the card is issued, what bank has issued the card and within the card network, what type of card it is, be it credit, debit, prepaid or a premium card.

All of the card networks have assigned numbers. The first digit is called the Major Industry Identifier and signifies the industry of the card issuer. The identifiers go from zero to nine and encompass various industries. If the card starts with a three, it's a travel and entertainment and financial services identifier, which is how American Express is classified. A four or five is from a banking and financial institution. If the card starts with a seven, it's a gas card.

The following digits then break down even further which type of card you have. If your card starts with a 51 to 55, you've got a MasterCard. Discover Cards have several designators, but if your card starts with a 6011, that's a way to tell you have Discover. Visas start with a four, and American Express cards start with a 34 or 37.

Beyond that, the digits do more to help each transaction route to the correct place. When the card is swiped, the system looks at each number in the IIN and is able to route the transaction to the correct card network and bank so that the bank can authorize the transaction.

In order for these numbers to function the way they do, they follow a standard created by the International Organization for Standardization. In the United States, the American Bankers Association is responsible for managing all bankcard numbers. "One element [for the standardization] is interoperability. It's a standardized account number that can be used in standard merchant systems," says Paterson.

The back of a credit card contains a magnetic stripe that contains account information, as well as security information. "There's a lot of data on the magnetic that the consumer can't see directly," says Paterson.

The back of the card also contains security features, including two security numbers known as CVV 1 and CVV 2. CVV stands for Card Verification Value and is a way to offer more security to the cardholder. The CVV 1 is encoded on the magnetic stripe and is checked during in-person transactions.

The CVV 2 number is the three-digit number located in the signature box on the back of the card. In the case of American Express, this is called the Card Identification number (CID) and is the four-digit number printed on the front of the card, above and to the right of the account number. Because the CID is not embossed and is printed directly on the card, one must have actual possession of the card in order to give out this number.

"It provides an independent number that's associated with the 16-digit account number," says Paterson. A stolen transaction might have the account number and expiration date, but they wouldn't have the CVV 2 number. Whoever is doing the transaction has the card in front of them and can flip it over [to verify the CVV 2 number]," says Paterson.

The CVV 2 number is reserved for use in "card not present" situations, or whenever you're conducting a transaction over the phone or online. Being able to give out that card number is a sign that you actually have the card on your person, rather than it being used by someone who's stolen it.

While you may think that the numbers on your credit card are simply a random assortment of digits, they do server a purpose more than just being your account number. They provide the means to make your credit card purchases happen, and they also give your card extra security to give you peace of mind.