I have been programming here and there since I was maybe nine years old. I'm 24 now, and I still don't feel like I'm good at it. I've made plenty of small, working programs, and I can translate any process I fully understand into an algorithm in a few minutes; but I hit a wall whenever I try to make - or to interpret - complex programs, because although each individual piece may make sense to me, the whole does not. I often have remarked to people that I wish programs were graphical and shaped like flow charts because maybe if I could visualize them, I could understand them better - but then there's the issue of clutter and so on...

Every time I've ever tried to make something complex, no matter how much I comment (and I comment a LOT), I've gotten to the point where I no longer understood my own program, even though every individual part of it made sense to me at the moment I had written it; and even simple stuff written by other people generally confuses me (particularly when it's not commented much) because I don't have the memory of having written it that with my own code is what enables me to go back to the mind state that led to its formation and thus understand how it works. (When I leave a program for a while and come back to it, that memory has usually faded and unless it's a rather simple algorithm, I usually struggle to recall why I wrote it the way I did.)

To be honest... I can write code easily, but I can't read it. It's like a weird form of illiteracy! And it's really holding me back, I think. How can I get over this problem? Are there resources for training oneself to understand programs that already exist, as opposed to creating new ones?