Hi, im a new Mac user, just got a Macbook Pro on Sunday, and so far I love it! However, I want to maintain it well, so I was wondering if it is better to put a mac in sleep mode over shutting it down...see, Im coming from PCs where shutting down is a must.....also, is it good to leave my macbook plugged into the wall for extended periods of time(a couple of days in a row)? Please, any help regarding this would be greatly appreciated!