Sketchup is a 3D modeling program used in architechure. I use Sketchup Make 2017, since it's the newest free version I could find that was still downloadable (the free version is browser-only these days).
I like to use it incorrectly. Case in point, this cat sculpture.
Sketchup is not good for making this kind of thing. This model took me many hours. But I had fun doing it, and that's what matters! (Although I probably should just learn Blender.)
Now, I did also use Sketchup for what it's actually made to do- architecture! ... Sorta.