# OS X Mountain Lion

OS X Mountain Lion (version 10.8) is the ninth major release of macOS, Apple Inc.'s desktop and server operating system for Macintosh computers. OS X Mountain Lion was released on July 25, 2012, for purchase and download through the Mac App Store, as part of a switch to releasing OS X versions online and every year, rather than every two years. Named to signify its status as a refinement of the previous OS X version, Lion, Apple's stated aims in developing Mountain Lion were to allow users to more easily manage and synchronise content between multiple Apple devices and to make the operating system more familiar.
The operating system gained the new malware-blocking system Gatekeeper and integration with Apple's online Game Center and iCloud services, while the Safari web browser was updated to version 6. As on iOS, Notes and Reminders became full applications, separate from Mail and Calendar, while the iChat application was replaced with a version of iOS's Messages. Mountain Lion also added a version of iOS's Notification Center, which groups updates from different applications in one place. Integrated links allowing the user to rapidly transfer content to Twitter were present in the operating system from launch. Facebook integration was also planned but unfinished at launch date. It was released as a downloadable update later.
OS X Mountain Lion received positive reviews, with critics praising Notification Center, Messages, and speed improvements over OS X Lion, while criticizing iCloud for unreliability and Game Center for lack of games. Mountain Lion sold three million units in the first four days, and has sold 28 million units as of June 10, 2013, making it Apple's most popular OS X release. Mountain Lion was the last paid upgrade for an OS X major release, with OS X Mavericks and later being free. Apple later allowed free downloads of the OS, especially for customers of older and no longer officially supported Macintosh computers, starting on June 30, 2021. The same practice was also applied to its predecessor, OS X Lion.

## History

OS X Mountain Lion was officially announced by Apple on their website on February 16, 2012, as a successor to Mac OS X Lion. It achieved golden master status on July 9, 2012.
During the Apple Worldwide Developers Conference keynote on June 11, 2012, Apple announced a "near final" release version of Mountain Lion for developers, with the public version arriving in July 2012 at a price tag of US$19.99 (€15.99 in Europe, £13.99 in the UK, $20.99 in Australia and ¥128 in Mainland China). The third generation MacBook Pro, revised MacBook Air, iPad Smart Case, and third-generation AirPort Express were announced at the keynote as well.
The specific release date of July 25 was not confirmed until the day before, July 24, by Apple CEO, Tim Cook, as part of Apple's 2012 third-quarter earnings announcement. It was released to the Mac App Store on July 25, 2012, where it sold 3 million units in the first four days of release.
An update for Mountain Lion, version 10.8.1, was released on August 23, 2012. It resolved issues with iMessages, Migration Assistant, Safari, Microsoft Exchange Server, Mail, and many other applications. Tests of the update revealed that 10.8.1 also improved battery life on laptops, albeit gaining back only half of the battery life that was lost in updating to Mountain Lion. Although 10.8.1 improved battery life for some customers, others continue to complain about reduced battery life and a constant drop in battery health, ultimately resulting in a "Service Battery" message.

## System requirements

The official system requirements of OS X 10.8 are 2 GB RAM, 8 GB available storage, Mac OS X 10.6.8 (Snow Leopard) or later, on any of the following Macs:
* iMac (Mid 2007 or later)
* MacBook (Aluminum, Late 2008 or later)
* MacBook Air (Late 2008 or later)
* MacBook Pro (Mid 2007 or later)
* Mac Mini (Early 2009 or later)
* Mac Pro (Early 2008 or later)
* Xserve (Early 2009)
As in 10.7, the earliest models supporting AirDrop are the early-2009 iMac, late-2008 MacBook, late-2010 MacBook Air, late-2008 MacBook Pro, mid-2010 Mac Mini, and early-2009 Mac Pro with an AirPort Extreme card. Any Mac released in or after 2011 supports AirPlay Mirroring. Power Nap is supported on the mid-2011 or newer MacBook Air and the MacBook Pro with Retina display.
The technical basis for these requirements is incompatibility with 32-bit EFI and 32-bit kernel extensions (most importantly, drivers for GPUs shipped in some older Macs). In order to prevent potentially incompatible systems from installing 10.8, the installer contains a whitelist of supported motherboard IDs. Users have bypassed these limitations so that 10.8 may run with varying functionality on some officially unsupported computers.

## New and changed features
### Default wallpaper

The default desktop picture is an image of the NGC 3190 galaxy.

### Notification Center

Notification Center was added in the operating system. It provides an overview of alerts from applications and displays notifications until the user completes an associated action, rather than requiring instant resolution. Users may choose what applications appear in Notification Center, and how they are handled. There are three types of notifications: banners, alerts, and badges. Banners are displayed for a short period of time in the upper right corner of the Mac's screen, and then slide off to the right. The icon of the application is displayed on the left side of the banner, while the message from the application will be displayed on the right side. Alerts are the same as banners, but will not disappear from the screen until the user takes action. Badges are red notification icons that are displayed on the application's icon. They indicate the number of items available for the application. It can be accessed by clicking the icon in the right corner of the menu bar. When open, the user can click a button to tweet, post status updates to Facebook, or view all notifications in the sidebar pane. Swiping up will reveal the option to disable Notification Center for one day. Many settings of Notification Center can be customized under the "Notifications" pane in System Preferences. Each application can have three ways to display notifications: none, banners, and alerts. Options to toggle the app icons and sounds are also available. Users can click and drag an app in the pane to change the order the applications are displayed within Notification Center.