• MacOS - How To Upgrade - Apple
• Mac Mountain Wallpaper
• MacOS - Wikipedia

Since the arrival of the Mac App Store in 2011 (as an update to Snow Leopard) versions of Mac OS X and macOS have been available to download via the Mac App Store. However, that changed slightly.

In this video, you’ll learn more about using the desktop in Mac OS X Mountain Lion. Visit https://www.gcflearnfree.org/macosxmountainlion/getting-started-wit. If you need to purchase Mac OS X 10.8 Mountain Lion, you may order it from this page. The current version of the Mac operating system is macOS Catalina. To learn more, please click here. What do you receive: An email with a content code for the Mac App Store. The first version of Mac OS X, Mac OS X Server 1.0, was a transitional product, featuring an interface resembling the classic Mac OS, though it was not compatible with software designed for the older system. Jul 25, 2012 When you install Mountain Lion or Lion, the installer creates an invisible, bootable, 650MB partition—a portion of a drive the operating system treats as a separate volume—on your startup drive.

Upgrade to macOS Big Sur

Before installing this upgrade, make sure that your Mac is ready.

Check compatibility

macOS Big Sur supports most Mac models introduced in 2013 and later.

Make a backup

Before you upgrade, make a complete backup with Time Machine, or store your files in iCloud.

Free up space

If the installer needs more storage space to upgrade, you can free up space using tools that come with your Mac.

Download macOS Big Sur

If you’re using macOS Mojave or later, choose Apple menu  > System Preferences, then click Software Update. If you’re using an earlier macOS, use the App Store instead.

Get to know macOS Big Sur

Learn about some of the new features of macOS Big Sur.

Control Center

Control Center brings favorite controls such as Bluetooth, Wi-Fi, Do Not Disturb, and Sound together in a single place—so you can easily adjust them at any time.

Notification Center

Notification Center puts notifications and>

Safari

Customize your start page, navigate with ease using the new tab bar, and access a new privacy report to see just how Safari protects your privacy as you browse.

Maps

Discover great places around the world and navigate easier with guides, cycling directions, indoor maps, Look Around, electric vehicle routing, and more.

Messages

Send messages to friends and family using new tools that make it easier to keep track of group conversations and give you fun, engaging ways to express yourself.

MacOS - How To Upgrade - Apple

Photos

Use the expanded editing capabilities in Photos to easily make simple changes and more advanced adjustments to your photos.

Have a question?

Ask everyone. Our Apple Support Community can help you find answers.

Tell us how we can help

Answer a few questions and we'll help you find a solution.

Start up from macOS Recovery

Determine whether you're using a Mac with Apple silicon, then follow the appropriate steps:

Apple silicon

Turn on your Mac and continue to press and hold the power button until you see the startup options window. Click the gear icon labeled Options, then click Continue.

Intel processor

Make sure that your Mac has a connection to the internet. Then turn on your Mac and immediately press and hold Command (⌘)-R until you see an Apple logo or other image.

If you're asked to select a user you know the password for, select the user, click Next, then enter their administrator password.

Reinstall macOS

Select Reinstall macOS from the utilities window in macOS Recovery, then click Continue and follow the onscreen instructions.

Follow these guidelines during installation:

• If the installer asks to unlock your disk, enter the password you use to log in to your Mac.
• If the installer doesn't see your disk, or it says that it can't install on your computer or volume, you might need to erase your disk first.
• If the installer offers you the choice between installing on Macintosh HD or Macintosh HD - Data, choose Macintosh HD.
• Allow installation to complete without putting your Mac to sleep or closing its lid. Your Mac might restart and show a progress bar several times, and the screen might be empty for minutes at a time.

After installation is complete, your Mac might restart to a setup assistant. If you're selling, trading in, or giving away your Mac, press Command-Q to quit the assistant without completing setup. Then click Shut Down. When the new owner starts up the Mac, they can use their own information to complete setup.

Other macOS installation options

Mac Mountain Wallpaper

When you install macOS from Recovery, you get the current version of the most recently installed macOS, with some exceptions:

• On an Intel-based Mac: If you use Shift-Option-Command-R during startup, you're offered the macOS that came with your Mac, or the closest version still available. If you use Option-Command-R during startup, in most cases you're offered the latest macOS that is compatible with your Mac. Otherwise you're offered the macOS that came with your Mac, or the closest version still available.
• If the Mac logic board was just replaced, you may be offered only the latest macOS that is compatible with your Mac. If you just erased your entire startup disk, you may be offered only the macOS that came with your Mac, or the closest version still available.

MacOS - Wikipedia

You can also use these methods to install macOS, if the macOS is compatible with your Mac:

• Use the App Store to download and install the latest macOS.
• Use the App Store or a web browser to download and install an earlier macOS.
• Use a USB flash drive or other secondary volume to create a bootable installer.