Smart cards are PVC cards embedded with smart chips designed to be encoded with identifying information. Smart chips contain memory, and for increased security, some also have a microprocessor. Available in both contact and contactless forms, smart cards are commonly used to control access to buildings and computer networks. Contactless smart cards combine smart chips with RFID technology, enabling them to communicate when placed within range of a reader. Contact smart cards transmit electronic data when they come into physical contact with a reader. Smart cards are about the size of a credit card. Many ID card printers are capable of encoding and printing smart cards.