Mac OSX BasicsMaking your transition to Mac seamless and painless.The following materials are provided by Apple.com.OSX Mountain Lion
Feature/Product:
Reading Material
Video Content
Switching to Mac from PC

http://www.apple.com/findouthow/mac/#switcher
Personalizing your Mac

http://www.apple.com/findouthow/mac/#personalizingmac
Finder

http://www.apple.com/findouthow/mac/#finderbasics
Gestures

http://www.apple.com/macosx/whatsnew/gestures.html
Expose

http://www.apple.com/findouthow/mac/#exposebasics
Screen Saver
http://www.apple.com/findouthow/mac/#screensaver

Air Drop
How to AirDrop - step by step