In the toolbar menu you can select the line, rectangle, circle, arc, eraser, tape measure (to measure distances, create guide lines or points, or scale a model), or paint bucket tool (assign materials and colors to entities - asphalt and concrete, blinds, bricks, carpets, metal, stone, and others).
Plus, the push/pull tool lets you push and pull Face entities, in order to add or substract volume from 3D models, and the move tool allows you to move, stretch or copy entities. The rotate tool enables you to rotate, stretch, distort, or copy entities along a rounded path, while the offset tool creates a copy of line at a uniform distance from originals.
You can also add photo textures to your model (a feature that uses Street View photos imported from Google Maps) - add a new building (by installing the Google Earth plugin), get models from the Internet, or share your own creations.
In conclusion, SketchUp proves to be a reliable and user-friendly program designed for 3D modeling.