Address books and contacts

See also Calendars; E-Mail, newsgroups, and forums.

Data interchange formats

 * h-adr (Microformats)
 * h-card (Microformats)
 * LDAP (Lightweight Directory Access Protocol)
 * LDIF (LDAP Data Interchange Format)
 * vCard (.vcf)

Program-specific formats

 * Cardfile (.crd)
 * Microsoft Outlook contacts: Stored as part of the Personal Folder File - See also Microsoft Outlook
 * Mozilla Thunderbird address book - See also Thunderbird
 * Notes Storage Facility (Lotus Notes; holds calendars, contacts, e-mail, and other things)
 * Novell GroupWise Address Book (.nab)
 * Pegasus Mail (has many file types including one for contacts)

Cell phone contact formats

 * AddressBook (Apple)
 * CDMA phone data
 * Google Contacts (cloud-based, used in Google services and synced to Android devices)
 * Nokia contact data
 * SIM contact data
 * Windows Mobile contact data