The Marvel Cinematic Universe is a franchise consisting of film and television adaptations of Marvel Comics publications produced by Marvel Studios. The franchise is notable for being the first superhero film franchise to have characters and plot points from different titles crossover.
Edwin Jarvis originates in the comics as Tony Stark's butler - the Alfred to Iron Man. However, in the MCU, JARVIS is an AI who assists Iron Man. Ostensibly, he is named after Edwin Jarvis, Howard Stark's butler, who appears in Agent Carter portrayed by James D'Arcy.