Google SketchUp, now simply known as SketchUp, is a 3D modeling software primarily used for architectural design, interior design, engineering, and other fields that require 3D visualization. Originally developed by @Last Software and later acquired by Google in 2006, it was rebranded as SketchUp and is now owned by Trimble. It's known for being user-friendly and accessible to beginners, while still offering robust tools for professionals.