Sketch up is a basic Modelling software that allows you to model something easy and fast.
This program is good for beginners to start learning basic 3D modelling. The 3d Software is developed By google. AAA title games like Uncharted used this program for basic layout for there environment.
What have I Used sketch up for?
I Use sketch up for rough modelling my ideas. The software was helpful for me to start my basic 3d modelling before I moved on to bigger and better 3d Software like 3dsMax.