If have been using Photoshop for a while now, you must had also notice the Mask Tool. But do you know what exactly it does and how and when should you decide to you use it?
You deleted everything from your USB key or a drive, so there should be enough free space to copy the new files, but you still get the not enough free space message in Mac OS X? This is what you need to do.
One of my all time favorite cartoons Monster Inc. just got a prequel called Monster University and the awesome Pixar guys showed us how the cartoon is made.
