It's a Virtual Business Card...
... but more specifically, a vCard is a file format standard for electronic business cards. vCards are often attached to e-mail messages, but can be exchanged in other ways, such as via the internet or instant messaging. They usually contain name and address information, organizational data, phone numbers, email addresses, website URLs and photographs.
vCard History
Versitcard was originally proposed in 1995 by the Versit Consortium, which consisted of Apple, AT&T Technologies (later Lucent), IBM and Siemens. In December 1996, ownership of the format was handed over to the Internet Mail Consortium, a trade association for companies with an interest in Internet e-mail.
Version 2.1 of the vCard standard is widely supported by e-mail clients. Version 3.0 of the vCard format is an IETF standards-track proposal contained in RFC 2425 and RFC 2426. Version 4.0 is defined in RFC 6350, with a new XML syntax, xCard, defined in RFC 6351. The commonly-used filename extension for vCards is vcf.