There is so many mixed information all over the internet. I am a little annoyed. So it's either do you need it or not? I am new to Mac. I need to make sure my computer is taken well care of. I don't want it to have files and things all over the place in the next 6 months and something happens. I don't download anything. it's all basic use. Internet, iWorks and iTunes. That's it. Windows you need it for sure. Used windows for over who knows how many years. BUT with a MAC no one can give a definite answer? Why is that? I getting confused and getting annoyed. First someone said that you don't need it as the computer does it for you 'overnight'. Then, there is some who says to do it every 2 weeks?