The Adventures of André & Wally B. (1:49)
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This was released in 1984, but as far as I recall I didn't see it until 2022. It's included on the Pixar Short Films Collection vol. 1, but it's not technically a Pixar short. It was made at Lucasfilm, by a team that would later found Pixar Animation Studios. It's a very short film without much of a story. A guy wakes up in a forest and gets briefly chased by a bee. That's it. There's no dialogue. Honestly, the short is only worth mentioning because it helped lead to the founding of Pixar (as a studio; it was originally a hardware company) and because the animation was revolutionary at the time it was made. Looking at it now, it's very primitive, but I'd say it does have historical significance.