If you experience an Mac OS X program to freeze and you cannot exit it by clicking quit or using a keyboard shortcut, you can always force it to quit using the Activity Monitor.
If you find yourself in a situation when you need to list your Mac specs or you just want know if you really got what you paid for, this is how you find them out.
If you are the kind of person you want to read what has been changed before updating an app you can disable the auto app update setting. Or enable if you want updates fully automated.
If you want to make a clean install of the new OS X Mavericks or even the older versions of Mac OS X, than I strongly suggest you to create a bootable OS X key or a drive.
Mac OS X Moutain Lion and its Safari web browser sharing options allow you to share and send any web page vie email as a PDF attachment in a matter of two clicks.
Sometimes you don't want your Mac OS X Mountain Lion powered computer to go to sleep, here's a nice little trick how to temporary prevent a Mac from going into a sleep mode.
