I just bought a Macbook last night, and entered the world of Mac for the first time. I installed a few programs, but I am not used to the procedures of installing on a mac. Whn you install a DMG file, you get a pop up that says, drag icon to the app folder, which I did. However, do I delete the leftover DMG file from my desktop once properly installed? Also, can I drag the apps to the desktop, like a PC, or leave it on the app folder?