Address book

The 1953 film version of Kiss Me, Kate features a musical scene in which Howard Keel's character laments the loss of the social life he enjoyed before marriage, naming numerous female romantic encounters while perusing a miniature black book, which has given rise to the trope of a little black book referring to a list of past or potential sexual partners.

Simple address books have been incorporated into email software for many years, though more advanced versions have emerged in the 1990s and beyond, and in mobile phones (a SIM card can store entries).

The common file formats for these operations are: Individual entries are frequently transferred as vCards (*.vcf), which are comparable to physical business cards.

This in turn enables users to be found by other people via a search of their name and then contacted via their web page containing their personal information.

Many people have many different address books: their email accounts, their mobile phone, and the "friends lists" on their social networking services.