Keycards are small, credit card-sized devices that use electronic technology to grant access to secure areas, like hotel rooms or office buildings. They contain a magnetic strip or a chip that communicates with a card reader when swiped or tapped. This makes it easy for authorized users to enter without needing traditional keys. These cards are often used in place of traditional locks because they can be easily reprogrammed. If a keycard is lost, it can be deactivated quickly, enhancing security. Many hotels and businesses use keycards to streamline access and improve safety for their guests and employees.