Could some of you post guides, or your own information, as to what factors go into selecting the correct component for a job in general? I think resistors are fairly well covered, but transistors and diodes can be more confusing, and theres a bit more to know about inductors and capacitors than whats obvious.
I've been doing a lot of pre drawn projects and tutorials, and I'm getting a sense of whats needed, but unfortunatly most of the guides say things like "use a P-Channel 350V 25Ohm Mosfet (part number) here" they don't often explain why that is the component for the job.
Oddly its easier to find guides that assume you know nothing at all, but once you've covered what a collector, base, and emmiter are they dont teach you much more. I'm looking for something that tells me some equations and guidelines, more at the level you would give a non-electrical engineer who needed to work with some electronics.