Awesome posts twospoons!!! Might I also humbly suggest that before @bloukingfisher try this on his Particle board, he does so on a breadboard with volt meter, testing to ensure everything is hooked up correctly so that he doesn't kill the Photon 
I've killed a few parts while learning to read circuits and implementing them 
Ha ha ha. How did you know about the time I accidentally wired in a 9V power supply to DAC or the reset pin? MULTIPLE TIMES! Actually from what I can tell everything worked fine, except for analogRead on A6 after that episode didn't seem to work quite right.
@twospoons your easy-to-access manner of education is superb, and thank you again for your explanations and time given. I didn't even imagine a decent free circuit simulator (I only tried a free one once, and it didn't have basic common transistors so I gave up on it).
In my early days as an engineer I managed to connect 12V to the reset line of a $100 microcontroller. It did not survive.
I’ve also destroyed a $1000 magnetic near-field probe, being incautious inside a power supply. This stuff happens to all of us.
As far as simulators are concerned, Simetrix has an extensive library to begin with, and adding more parts is usually as simple as drag and drop with a new SPICE model file. Its one of the things that makes it so easy to use.
The only problem is that some silicon vendors are not providing generic spice models any more ( I’m looking at YOU, TI!).
If you want some further reading on analog electronics, I can thoroughly recommend “The Art of Electronics” by Horowitz and Hill.