Thank you! That's a good one, we should do a post just on mining. And honestly, maybe begin compiling an illustrated glossary of terms. I believe nodes are witnesses. But will need to double (triple) check...
Also, we just did a post today on Witnesses that covers the uber basice but you might find useful - https://steemit.com/toolkit/@sndbox/what-is-a-steem-witness-introducing-the-basics