Not sure where else to ask this, so I figured I'd give good old stackoverflow a shot.
Let's say, by chance, I would like to write a library or set of libraries that will create PDF's and convert files to PDF, AND I could care less about how long it will take me to complete (3 months - 10 years.. whatever). I have absolutely no interest in paying for a toolkit... the point of this would be to learn how to manipulate and create files like PDF's. There's nothing business critical about the project, I just want to learn how to do it. Where do I start? I would imagine something like this would be written in C++, but I'm not sure... maybe high level languages would work as well. I'm not looking for someone to tell me exactly how to do it, but send me in the write direction, or at least point out the concepts I would need to concretely grasp before proceeding with such a project.
Any advice and help in directing me here is greatly appreciated : )