Tag or tagging may refer to:

Personal identifiers

• Dog tag, a small, flat, metal identification label attached to a dog collar
• Dog tag (identifier), a small, flat, metal identification label worn around the neck of military personnel
• Triage tag, a tool used by first responders and medical personnel at mass casualty incidents
• A form of signature used by graffiti artists
• Another name for license plate

Computing

• TAG (BBS), a DOS-based bulletin board system software program
• Tag (metadata), a keyword or term associated with or assigned to a piece of information
• Tag system, a deterministic computational model
• Electronic tagging, a form of non-surreptitious surveillance
• Revision tag, a textual label associated with a specific revision of a project
• HTML tag, part of an Hypertext Markup Language document

Corporations and organizations

• Tactical Assault Group, an Australian counter-terrorism force
• Technical Architecture Group, a W3C body created to document and build consensus around principles of Web architecture
• Techniques d'Avant Garde, a Luxembourgian private holding company
• TAG Heuer, a Swiss watchmaker
• TAG Recordings, a record label
• TAG Entertainment, a United States movie production company
• Transportes Aereos Guatemaltecos, a Guatemalan private passenger and cargo airline
• Treatment Action Group, an American HIV/AIDS activist organization
• Talal Abu-Ghazaleh Organization, an international holding firm

Education and language

• Part-of-speech tagging, the process of marking up words as corresponding to a particular part of speech
• Talented and Gifted program, an American education curriculum
• Tree-adjoining grammar in computational linguistics
• School for the Talented and Gifted, Dallas, Texas, USA

Sports and Entertainment

• Tag (game), an informal playground game involving chasing and touching
• Tag out, a play in baseball
• Tag (comics), the fictional character Brian Cruz
• TaG, Touch and Go class in karting
• Tag team, a group of two or more professional wrestlers

Transportation

• Tennessee, Alabama and Georgia Railway, a reporting mark
• The name of the Free Flow, a traffic toll payment system in Spanish-speaking countries

Science and technology

• TAG (Magazine), a technology and lifestyle magazine
• Skin tag, a small benign skin tumour
• Theoretical and Applied Genetics, a scientific journal
• Trans Austria Gas Pipeline
• Triglyceride (triacylglycerol or triacylglyceride), esterified glyserol
• Topological abelian group in mathematics

Other uses

• Tag (Barbershop), the last section of a barbershop music song
• TAG Body Spray, a Gillette product
• Timneh African Grey, the smaller of the two sub-species of African Grey parrot
• Transcendental argument for the existence of God

See also

• Tagline, a form of advertising slogan

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