Pat Hanrahan is a very smart and important computer scientist who teaches and does research at Stanford University. He helped create some very cool things that we use on computers and in movies.
When we watch movies or play video games with really cool special effects, Pat may have had something to do with that. He helped create a way for computers to make things look more real and detailed, even when they're not really there. It's like making a fake movie set look like a real place!
But Pat also does other cool things with computers. For example, he created a way for people to make 3D models of things on their computers. So instead of just looking at a flat picture of something, we can use special software to make it look like it's popping out of the screen! That's why sometimes you might see a picture of an animal that looks like it could jump right off the page.
Overall, Pat Hanrahan is a really smart and creative person who helps make the things we see on computers look better and more interesting.