OS X 10.8 Mountain Lion is the ninth major release of Apple's OS X operating system.

OS X 10.8 Mountain Lion is the ninth major version of OS X, and the eight major upgrade since Mac OS X 10.0.

Mountain Lion was released through the Mac App Store on Lion and Snow Leopard on July 25th, 2012 for $19.99/£13.99.

Mountain Lion carries forward Mac OS X Lion's objective, i.e. to bring iOS features to Mac. Such features include the Notification Center, iCloud, Twitter and Facebook integration, Power Nap (on 2012 MacBook Air/Pro retinas), AirPlay Mirroring, iMessage, Reminder, Notes, and Game Center. iCloud is now a full-fledged replacement for MobileMe by providing multi-platform sync between iPhone, iPad, iPod touch and Mac. Mountain Lion's dictation feature also brings a 'Siri-like' element to the field even though it lacks the ability to operate on commands.

OS X Mountain Lion requires an Intel Core 2 Duo or newer, and one of these Macs:

  • iMac (Mid 2007 or newer)
  • MacBook (Late 2008 Aluminum, or Early 2009 or newer)
  • MacBook Pro (Mid/Late 2007 or newer)
  • MacBook Air (Late 2008or newer)
  • Mac mini (Early 2009 or newer)
  • Mac Pro (Early 2008 or newer)
  • Xserve (Early 2009)

However, not all Macs can handle AirPlay Mirroring. The following Macs are required to mirror to an Apple TV:

  • iMac (Mid 2011 or newer)
  • Mac mini (Mid 2011 or newer)
  • MacBook Air (Mid 2011 or newer)
  • MacBook Pro (Early 2011 or newer)

Whereas Lion removed the word 'Mac' from all marketing materials, Mountain Lion has completely removed 'Mac' in the system as well, making the final name "OS X Mountain Lion".