The previous tutorial showed us how we can draw a triangle to the screen. However, it came with a disclaimer. Even though it works, it's not the "correct" way to do things anymore. The way we sent our geometry to the GPU was what's known as "immediate mode", which isn't the newest way to do things, even if it is so very nice and simple.
In this tutorial, we'll be going for the same end goal, but we'll be doing things in a way that is more complex, but at the same time more efficient, faster, and more expandable.