I've seen a few Hearthstone matches, but haven't played it myself. It seems very similar to MtG, except for some missing mechanics, like cards that you can play on your opponent's turn.
I can wholeheartedly recommend "Magic the Gathering: Duels of the Planeswalkers 2014" for the uninitiated. It seems to be going for 5€ on Steam at the moment. I had played a few physical card games before trying the digital game, but I went through the tutorial anyway. I found the tutorial very efficient and comprehensive and fun, so it's a great way to learn the rules at your own pace.