J.A.R.V.I.S. is the name of a A.I. created by Tony Stark.
J.A.R.V.I.S. was inspired by Edwin Jarvis, Tony Stark's butler (originally introduced as a butler to the Avengers).
J.A.R.V.I.S. was created for the film Iron Man (2008) from the Marvel Cinematic Universe. J.A.R.V.I.S. was created to avoid comparisons with Alfred Pennyworth, butler of Bruce Wayne/ Batman and was inspired by other AIs used by Stark like Friday, HOMER and PLATO.
The acronym Just A Rather Very Intelligent System appears in the novelization of the Iron Man written by Peter David.
Interestingly, an artificial intelligence named Jarvis (no acronym) had appeared in Iron Man: House of M (2005), written Greg Pak and illustrated by Pat Lee.
J.A.R.V.I.S. was adapted for the main universe in Invincible Iron Man (Vol. 2) #11 (March, 2009), written by Matt Fraction and illustrated by Salvador Larroca.
The Avenger's Earth Mightiest Heroes
J.A.R.V.I.S. appears as an A.I. program inside Tony's suit, voiced by Phil LaMarr.
Iron Man: Armored Adventures
J.A.R.V.I.S. appears as the A.I. inside Andros Stark's Iron Man 2099 armor.
J.A.R.V.I.S. appears as Tony's A.I. once again, voiced by David Kaye.
In the Marvel Cinematic Universe, Tony's Artificial Intelligence program is called J.A.R.V.I.S., a reference to Edwin Jarvis from the comics.
J.A.R.V.I.S. is inside Tony's suit, and can talk with Tony. He also manages things inside Tony's home. It was revealed JARVIS is an acronym for "Just A Rather Very Intelligent System". J.A.R.V.I.S. is voiced by English actor Paul Bettany.
The prequel comic Iron Man 2: Public Identity reveals that Edwin Jarvis was Tony's childhood butler, and that after his death, Tony named the J.A.R.V.I.S. A.I. after him as a way to honor his memory.
J.A.R.VI.S. is seemingly destroyed by Ultron in Avengers: Age of Ultron, leading to Tony using a replacement AI called F.R.I.D.A.Y. It is later revealed that fragments of J.AR.V.I.S. survived, and Tony uses them to create the Vision.
Tony Stark and Steve Rogers travel through time and meet Howard Stark (John Slattery) and Edwin Jarvis (James D'Arcy).