By default, all software supports multiple file extensions. Mac OS X Address Book (Contacts) supports at least 7 different file extensions. The basic files that Mac OS X Address Book (Contacts) supports are .VCF. However, not all of the extensions listed on the list are always used to save the effects of work in Mac OS X Address Book (Contacts). Very often, files with such extensions are used as source data files used by Mac OS X Address Book (Contacts).
Mac OS X Address Book (Contacts) can be used to convert file formats between the file extensions listed below. You can open a file with one of the file extensions below via Mac OS X Address Book (Contacts) and try to save it in another file format, also supported by Mac OS X Address Book (Contacts).