In the first Shrek (2001), the animation of Shrek taking a mud shower was a huge technical milestone. At the time, "fluid and particle simulation" (like mud or water) was one of the hardest things to do in 3D animation.
The lions in 'The Lion King' don't actually roar. Since real lion roars were too quiet, the producers used tiger roars instead.
'Snow White and the Seven Dwarfs' was the first animated feature. Walt Disney received one full-size Oscar and seven mini-ones for it!
First appearing in Toy Story, the yellow Gyoza Mark VII Lite Hauler (the Pizza Planet truck) has been hidden in nearly every Pixar movie since, including Brave (as a wood carving) and WALL-E (as a piece of junk).
To make the snow in Frozen look real, Disney engineers actually created a new software called "Matterhorn." They studied how snow packs and breaks by consulting with real-world avalanche experts and physicists.
In Zootopia, there are 64 different species of animals. Instead of using the same "digital fur" for all of them, animators studied hair under a microscope. A polar bear's fur is actually clear and hollow, while a fox’s fur is dark at the root—and they replicated this exactly in the code.