So far, we've seen how to set up our OpenGL renderer and draw some very basic geometry. But, as you can imagine, we can do a lot more with OpenGL. In this section we'll see how to do some more complex operations and how to load geometry defined using an external tool. Sometimes, it might come in useful to define the geometry using code, but most of the time, and especially if the geometry is very complex, it'll be designed and created using a 3D modeling tool. Knowing how we can import that geometry will definitely come in very handy for our projects.