The DC Animated Universe (DCAU) was made up of:
Batman: The Animated Series
Superman: The Animated Series
Batman Beyond
Static Shock
The Zeta Project
Justice League
Justice League Unlimited
Batman: Mask of the Phantasm
Batman & Mr. Freeze: SubZero
Batman: Mystery of the Batwoman
Batman Beyond: Return of the Joker
The following TV series are all stand alone series, and are not connected to anything else, thus you can view them in any order, or not view them at all & you won't miss a thing in other series:
Teen Titans (the film Teen Titans: Trouble in Tokyo is a finale to this series)
The Batman
Krypto the Superdog
Legion of Super Heroes
Batman: The Brave and the Bold
Young Justice
Green Lantern: The Animated Series
DC Nation Shorts
Beware the Batman
Teen Titans Go!
The DC Universe Animated Original Movies used to be stand alone films, and the ones that were not connected to anything else are:
Superman: Doomsday
Justice League: The New Frontier
Batman: Gotham Knight
Wonder Woman
Green Lantern: First Flight
Superman/Batman: Public Enemies
Justice League: Crisis on Two Earths
Batman: Under the Red Hood
Superman/Batman: Apocalypse (this is a sequel to Superman/Batman: Public Enemies)
Superman/Shazam!: The Return of Black Adam
All-Star Superman
Green Lantern: Emerald Knights
Batman: Year One
Justice League: Doom
Superman vs. The Elite
Batman: The Dark Knight Returns - Part 1
Batman: The Dark Knight Returns - Part 2 (these 2 are linked to each other)
Superman: Unbound
JLA Adventures: Trapped In Time
Justice League: The Flashpoint Paradox (this film sets up the New 52 films)
Batman: Assault on Arkham (set in the Batman: Arkham videogame universe, but can be watched even if you've never played any of the games)
The DC Animated Film Universe is made up of movies which are adaptions of the comics' New 52 universe, and as such ARE connected in continuity with each other. They are:
Justice League: War
Son of Batman
Justice League: Throne of Atlantis
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