i am new in the apple world. I'm coming from pc + ubuntu. I've just bought a Mac Book Pro 13" with 2.5 Ghz Inter Core i5 and ram 4 GB. I am suspicious something is wrong because it i have only skype, chrome, safari, and some other software (a programming light text editor like Sublime text editor) and few other things I listen a continuously little whirr, like when data are read/writte from harddisk. So i opened Activity Monitor and i've seen few peeks in Disk Activity.

I am suspicious that this is smothing wrong with my new mac book. how can i diagnosticate better what is happening? is it normal?
