Maybe you don’t need to know, but every programmer worth his salt should know what they are and how they work, even if not actually building them himself. I remember when I studied my computer science I was asked to build my own software rasterizer and thought to myself “When am I ever going to need to do this? This is why we have game engines that do it for us”. But looking back, I’m glad I did because it gives you valuable insight into why things work the way they do. I can guarantee that if you do, at some point you will have that difficult how-to question and you won’t be looking on a forum, you will be the one answering it.
If you’re new to programming, don’t kick yourself if you don’t get it 100%. We all went through that at some point.