Both these question confuse Mana and Land in magic-the-gathering. Do I have to take mana from my deck or hand when tapping a dual land? How do dual lands and their mana work? Is it worth making one of these the cannonical QA for this type of question?

I've noticed that when I go to the "Review" section to look at things such as new answers in the queue, I sometimes have different options than other times. Just now I was looking at an answer under the "New answer to old question" queue. I had options for "skip" or "no action needed". But there...