These are something that has confused me for quite some time. Just like a lot of you, I'm sure, I'm a tinkerer. I like to take things apart, salvage parts, etc. A lot of stuff I take apart have a triac for AC control (a good example is a broken heater fan I'm trying to fix, but the triac isn't the issue there).
I know (or I think I know) that a triac is used for phase control of AC circuits, but I always see them used with a diac in schematics, and that's where the main confusion comes in. In almost everything I've taken apart with a triac in it, there's no specific component that comes up as a diac (when I look up part numbers).
My understanding is that a diac can simply be two regular schottky diodes in parallel with reverse polarities, is this true? I'm not overly fond of the idea of trying it with live AC without understanding it a little better. I'd like to phase-control a 120V resistive heating element (or more than one, if possible) and I just want to be more comfortable with what I'm doing. The internet keeps contradicting itself with the information I find.