FOAF

{{Short description|Semantic Web ontology to describe relations between people}}

{{for|"friend of a friend"|friend of a friend|Friend of a Friend (disambiguation)}}

{{Infobox technology standard

|image=FoafLogo.svg

|image_size=120px

|caption=FOAF logo

|status=Published

|title=FOAF

|native_name=

|series=Namespace Document

|abbreviation=FOAF

|organization=

|authors=Dan Brickley, Libby Miller

|domain=Semantic Web

|base_standards=RDF, OWL

|first_published={{Start date and age|2005|06|03}}

|year_started={{Start date and age|2000}}

|version=0.99

|version_date={{Start date and age|2014|1|14}}

|license=CC BY 1.0

|website={{URL|http://xmlns.com/foaf/spec/}}

|long_name=Friend of a friend}}

FOAF (an acronym of friend of a friend) is a machine-readable ontology describing persons, their activities and their relations to other people and objects. Anyone can use FOAF to describe themselves. FOAF allows groups of people to describe social networks without the need for a centralised database.

FOAF is a descriptive vocabulary expressed using the Resource Description Framework (RDF) and the Web Ontology Language (OWL). Computers may use these FOAF profiles to find, for example, all people living in Europe, or to list all people both you and a friend of yours know.[https://web.archive.org/web/20091223003446/http://www.ibm.com/developerworks/xml/library/x-foaf.html XML Watch: Finding friends with XML and RDF] by Edd Dumbill in IBM DeveloperWorks[https://web.archive.org/web/20100307223814/http://www.ibm.com/developerworks/xml/library/x-foaf2.html XML Watch: Support online communities with FOAF] by Edd Dumbill in IBM DeveloperWorks This is accomplished by defining relationships between people. Each profile has a unique identifier (such as the person's e-mail addresses, international telephone number, Facebook account name, a Jabber ID, or a URI of the homepage or weblog of the person), which is used when defining these relationships.

The FOAF project, which defines and extends the vocabulary of a FOAF profile, was started in 2000 by Libby Miller and Dan Brickley. It can be considered the first Social Semantic Web application,{{citation needed|date=April 2017}} in that it combines RDF technology with 'social web' concerns.{{clarify|date=April 2017}}

Tim Berners-Lee, in a 2007 essay,{{cite web |website=Decentralized Information Group |url=http://dig.csail.mit.edu/breadcrumbs/node/215 |title=Giant Global Graph |first=Tim |last=Berners Lee |archive-url=https://web.archive.org/web/20160713021037/http://dig.csail.mit.edu/breadcrumbs/node/215 |archive-date=2016-07-13}} redefined the semantic web concept into the Giant Global Graph (GGG), where relationships transcend networks and documents. He considers the GGG to be on equal ground with the Internet and the World Wide Web, stating that "I express my network in a FOAF file, and that is a start of the revolution."

WebID

FOAF is one of the key components of the WebID specifications, in particular for the WebID+TLS protocol, which was formerly known as FOAF+SSL.

Deployment

Although it is a relatively simple use-case and standard, FOAF has had limited adoption on the web. For example, the Live Journal and DeadJournal blogging sites support FOAF profiles for all their members,{{cite web |website=LiveJournal |title=LiveJournal FOAF |url=http://community.livejournal.com/ljfoaf |archive-url=https://web.archive.org/web/20100118151037/http://community.livejournal.com/ljfoaf |archive-date=2010-01-18}}. My Opera community supported FOAF profiles for members as well as groups. FOAF support is present on Identi.ca, FriendFeed, WordPress and TypePad services.{{cite web|url=http://wiki.foaf-project.org/w/DataSources |title=Known FOAF data providers |publisher=FOAF project |url-status=dead |archiveurl=https://web.archive.org/web/20100226072731/http://wiki.foaf-project.org/w/DataSources |archivedate=2010-02-26 }}

Yandex blog search platform supports search over FOAF profile information.{{cite web|date=2008-08-15|title=press release on the social networking support|url=http://company.yandex.com/press_center/press_releases/2008/2008-08-15.xml|publisher=Yandex}} Prominent client-side FOAF support was available in Safari{{cite web | publisher = eJohn | url = http://ejohn.org/blog/foaf-support-in-safari-rss/ | title = FOAF Support in Safari RSS}}. web browser before RSS support was removed in Safari 6 and in the Semantic Radar{{cite web | url = https://addons.mozilla.org/en-US/firefox/addon/semantic-radar/ | title = Semantic Radar plugin for the Firefox browser | publisher = Mozilla | access-date = 2012-02-20 | archive-url = https://web.archive.org/web/20140108014347/https://addons.mozilla.org/en-US/firefox/addon/semantic-radar/ | archive-date = 2014-01-08 | url-status = dead }} plugin for Firefox browser. Semantic MediaWiki, the semantic annotation and linked data extension of MediaWiki supports mapping properties to external ontologies, including FOAF which is enabled by default.

There are also modules or plugins to support FOAF profiles or FOAF+SSL authorization for programming languages,{{cite web | publisher = CPAN | url = https://metacpan.org/pod/XML::FOAF | title = FOAF support module for Perl}}{{cite web | publisher = CPAN | url = https://metacpan.org/pod/Web::ID | title = FOAF+SSL authentication support for Perl}} as well as for content management systems.http://drupal.org/project/foaf - FOAF support for Drupal

Example

The following FOAF profile (written in Turtle format) states that James Wales is the name of the person described here. His e-mail address, homepage and depiction are web resources, which means that each can be described using RDF as well. He has Wikimedia as an interest, and knows Angela Beesley (which is the name of a 'Person' resource).

@prefix rdf: .

@prefix rdfs: .

@prefix foaf: .

<#JW>

a foaf:Person ;

foaf:name "James Wales" ;

foaf:mbox ;

foaf:homepage ;

foaf:nick "Jimbo" ;

foaf:depiction ;

foaf:interest ;

foaf:knows [

a foaf:Person ;

foaf:name "Angela Beesley"

] .

rdfs:label "Wikimedia" .

History

=Versions=

class="wikitable sortable" \|+ Versions table
Version ! Date ! namespace URI ! Description
{{Version \|o \|0.98}} \| {{dts\|2010-08-09}} \| http://xmlns.com/foaf/0.1/
{{Version \|c \|0.99}} \| {{dts\|2014-01-14}}{{cite web \| last1 = Brickley \| first1 = Dan \| author-link1 = \| last2 = Miller \| first2 = Libby \| author-link2 = \| date = 2014-01-14 \| title = FOAF Vocabulary Specification 0.99 \| work = xmlns.com \| publisher = FOAF project \| url = http://xmlns.com/foaf/spec/20140114.html \| access-date = 2022-03-31 \| archive-url = https://web.archive.org/web/20220303180551/http://xmlns.com/foaf/spec/20140114.html \| archive-date = 2022-03-03 \| url-status = live }} \| http://xmlns.com/foaf/0.1/ \| Current version Paddington Edition
colspan=4 \| {{Version\|l\|show=010100}}

class="wikitable sortable"

|+ Versions table

Version

! Date

! namespace URI

! Description

| {{dts|2010-08-09}}

| http://xmlns.com/foaf/0.1/

| {{dts|2014-01-14}}{{cite web

| last1 = Brickley

| first1 = Dan

| author-link1 =

| last2 = Miller

| first2 = Libby

| author-link2 =

| date = 2014-01-14

| title = FOAF Vocabulary Specification 0.99

| work = xmlns.com

| publisher = FOAF project

| url = http://xmlns.com/foaf/spec/20140114.html

| access-date = 2022-03-31

| archive-url = https://web.archive.org/web/20220303180551/http://xmlns.com/foaf/spec/20140114.html

| archive-date = 2022-03-03

| url-status = live

}}

| http://xmlns.com/foaf/0.1/

| Current version

Paddington Edition

colspan=4 | {{Version|l|show=010100}}

References

External links

{{Official website|http://www.foaf-project.org}} ({{Webarchive |url=https://web.archive.org/web/20211023122305/http://www.foaf-project.org/ |date=23 October 2021}})
[http://ebiquity.umbc.edu/resource/html/id/82/ FOAF dataset] a dataset of 201,612 FOAF triples
Archived: {{webarchive |url=https://web.archive.org/web/20181130195340/https://www.foaf-search.net/ |date=Nov. 30, 2018 |title= FOAF-search - a search engine for FOAF data }}

Category:Ontology_(information_science)

Category:Semantic Web

Category:2000 software