Calypso is an international electronic ticketing standard for microprocessor contactless smart cards, originally designed by a group of transit operators from 11 countries including Belgium, Canada, France, Germany, Italy, Latvia, México, Portugal and others.
Calypso was born in 1993 from a partnership between the Paris transit operator RATP and Innovatron, a company owned by the French smartcard inventor, Roland Moreno.
Most European transit operators from Belgium, Germany, France, Italy and Portugal eventually joined the group in the following years.
Therefore, despite their closeness, there are few significant differences between Calypso's historical contactless protocol and ISO/IEC 14443 Type B international standard.
has a microprocessor which contains all the information related to its owner rights for the application, and which implements the Calypso authentication scheme for security.