I agree with Batman (I feel ridiculous saying that).
Those 2 principles should be the first things learned after knowing how the pieces move. It's the 2 things new chess players usually do wrong and a bad opening quickly evolves in a very difficult game.
I started playing chess 4 years ago on chess.com and I am not improving. In the last 3 months I have made a more concerted effort but if anything I am getting worse. I am writing about this recent quest to improve my chess at my chess blog www.chessluddite.com and I would love suggestions about what might work. I think computers are perfect training tools for chess but ideally I would like suggestions that don't involve computers (a lifestyle thing). What training methods have worked for you? Do you have a chess routine or workout?