AAA (Almost Anything Awesome) Nodes can drastically speed up your design workflow while at the same time allowing you to work non-destructively. Sometimes you might also want to add more complexity to your scene super-fast, and now you can by connecting two or more nodes. There are other similar solutions out there that you should definitely check out, for example Erindale Toolkit. Highly recommended.
Before you start using AAA nodes, keep in mind that most of them won't give you an instant result, unless you apply them to a geometry that you've already placed in the scene. If you want to work 100% procedurally, you will have to start with AAA Primitives, such as AAA (1) Curve and AAA (1) Profile Curves. You can plug primitives into other nodes to generate a geometry with vertices, edges and faces. For example, you can combine AAA (1) Curve and AAA (1) Profile Curves (any available shape) with AAA (3) Curve Master that has both the 'Curve Socket' and the 'Profile Curve Socket'.
When you're happy with your creation, feel free to convert it to a real geometry which you can edit in a more traditional manner. This is very convenient when you want to generate simple assets for your scene. AAA nodes are also great for animation and motion graphics because all the parametric values can be keyframed. You can test it by typing #frame or #frame/35 (or any other value) in any of the value fields and press spacebar to start the animation (Esc to stop and reset it). To delete the value you entered, just go over the slider, right click and choose 'Delete Driver'.