"A proximity card contains information stored electronically within the card. The information is transmitted via radio over a short distance (typically less than 10 centimeters) after the card is queried. Users like these cards because they require very few steps to perform authentication and therefore are quite fast. These cards are vulnerable to physical attacks that extract data from them. They also may be susceptible to interception of the transmitted data (over a short distance) and to spoofing attacks, in which the attacker transmits the same sort of query as a legitimate verifier and records the response. For disabled users, proximity cards may be attractive alternatives to magnetic stripe cards since card readers for the former have instructions that are typically visual, they are not always located in positions accessible to those in wheelchairs, and they are hard to insert for those whose manual dexterity is poor."