Indonesian language, ISO 639 alpha-2 code id

In India, the Muslim religious festival of Id-ul-Fitr

the United States postal abbreviation for Idaho

Identity card, a card used to establish positive identification of an individual

The Citroën ID, a variant of the Citroën DS

id Software, the computer game software developer

Industrial design

the id in the Id, ego, and super-ego psychological construct

Influence diagram, a graphical and mathematical representation of a decision situation

i-D, a British fashion magazine

I.D. (film), the 1995 British film, directed by Philip Davis

An identity function, a function that always returns the same value that was used as its argument.

Internet Draft, a working document of the IETF

an abbreviation for the Latin idem.

I.D. (magazine), and American magazine focusing on Architecture, Graphic and Industrial Design

iD Two, RTÉ television programme

iD (video game), is a 1980s video game by Mel Croucher

Inside diameter, a dimension commonly used to specify the size of tubing or pipe

Intelligent design, a modern form of the teleological argument (an argument for the existence of a god) which argues that life was designed

Indonesia, ISO 3166-1 alpha-2 country code ID (Internet TLD: .id)

Interlink Airlines, IATA airline code

in the Objective-C programming language id is the designation of the generic object datatype