If you're like me, then you probably are just a tad (shya!) baffled by all the knobs and buttons associated with a synthesizer. When I was a kid, I certainly could not afford a real, hardware synthesizer. And by the time I was recording regularly, most of them were already digitized into software versions of their hardware predecessors.
I like playing with them, but I still don't really know what all the little knobs mean. My latest experience with this was just last week when I downloaded the new Magellan Synthesizer (see picture on the left) from the Apple App store to my iPad 2 for - wait for it - a whole 5 bucks! Un-freakin'-believable. It comes, as many synths do, with lots of preset sounds. So you can spend hours just picking those and playing with them without having to worry about the knobs and sliders.
But the way these instruments work is that they have things called oscillators, which are sound sources. Then through some combination of filters and other wave-altering tools, you can create any number of cool sounds, which can then be used to make music (or frighten the cat, depending on your desired outcome).
If you have started working with synthesizers like these (not to be confused with samplers, sometimes called soft-synths, which really just allow you to play and manipulate audio that was sampled (recorded) from actual instruments), then you might be interested in some of the cool creative things you can do with them. The real fun happens when you move beyond the presets and start to create you OWN sounds.
You can learn about some of these ideas in this video by Mo Volans. This one uses the Thor Synthesizer, which comes with the Propellerhead Reason recording software. But the concepts can be applied to any synth.