AVS stands for Address Verification System and is a security mechanism used with online card payments. The main idea is to compare the provided address information with the customer billing information associated with the card. AVS is designed to minimize fraudulent non face-to-face cards transactions.
The system is also flexible enough to allow simple mistakes (for example making a typo in a street name doesn't have to be considered a typo) and define the sensitivity using a variety of result codes. AVS is available only in specific countries.