The Marvel Cinematic Universe is a media franchise created by Marvel Studios, set primarily in a shared universe designated as the reality Earth-199999 within Marvel's multiverse system, with some installments also set in adjacents or branching realities. The franchise includes comic books, short films, television series, and digital series. The shared universe, much like the original Marvel Universe in comic books, was established by crossing over common plot elements, settings, cast, and characters.

Starting with Iron Man, the franchise is comprised mainly of films independently made by Marvel Studios, that are primarily set within this same universe, much like Marvel has done with their comics. The franchise includes a series of short films, called Marvel One-Shots, launched with each film's Blu-ray release starting with Thor and finishing with Thor: The Dark World. Starting with Agents of S.H.I.E.L.D., the franchise expanded into television series, including series premiered on the ABC and Freeform channels, and on the Netflix, Hulu, and Disney+ streaming platforms. The franchise also includes the news program WHiH Newsfront and the digital series Agents of S.H.I.E.L.D.: Slingshot. Other contents include a series of tie-in Comics and video games, released as promotional material to the films, all set within the same reality. However, some of them, especially video games, do not match the events featured in other products following their release and are classified as non-canonical in this universe.