Data formats typically used for the exchange of personal information typically found on a traditional business card, to-do list, or calendar, as well as formats that are aggregates of collections of these.
iCalendar is a standard for calendar data exchange. The standard is sometimes referred to as "iCal", which also is the name of the Apple Computer calendar program that provides one of the implementations of the standard.
vCalendar is an exchange format for personal scheduling information. It is applicable to a wide variety of calendaring and scheduling products and useful in exchanging information across a broad range of transport methods.