Geez ..what a merry bunch. Anyway here's a basic guide: https://area.autodesk.com/userdata/fo...GPW49V3hFT.pdf I don't think it's very helpful to learn about rendering by changing a value after value and re-rendering as a lot of the changes will be very hard to notice if you don't know what you're looking for and some will only affect specific effects that you might be missing in your scene. On the other hand I agree that it's a huge topic, so just pick one value and ask about it, unless you want to get slaughtered here..