Various macOS Startup Modes Explained

Mac startup key combinations

• Command (⌘)-R: Start up from the built-in macOS Recovery system. ...
• Option (⌥) or Alt: Start up to Startup Manager, which allows you to choose other available startup disks or volumes. ...
• Option-Command-P-R: Reset NVRAM or PRAM. ...
• Shift (⇧): Start up in safe mode. ...
• D:

1. What does Command's do on a Mac at startup?
2. How do I choose my startup disk Mac?
3. What are the levels of Mac OS?
4. What is Safeboot mode?
5. What is command R on Mac?
6. What is the Command and R keys on a Mac?
7. How do I choose my operating system on startup?
8. Can I boot my iMac from an external SSD?
9. How do you clean your startup disk on a Mac?
10. Which Mac operating system is best?
11. What is macOS written in?
12. Is Catalina better than Mojave?

What does Command's do on a Mac at startup?

Holding down Command + S during startup will boot your Mac into Single User Mode. This is a terminal interface that allows you to login and interact with your computer via text input only.

How do I choose my startup disk Mac?

Change your startup disk for every startup

On your Mac, choose Apple menu > System Preferences, then click Startup Disk. If the lock at the bottom left is locked , click it to unlock the preference pane. Click the icon of the disk you want to use, then click Restart.

What are the levels of Mac OS?

Meet Catalina: Apple's newest MacOS

• MacOS 10.14: Mojave- 2018.
• MacOS 10.13: High Sierra- 2017.
• MacOS 10.12: Sierra- 2016.
• OS X 10.11: El Capitan- 2015.
• OS X 10.10: Yosemite-2014.
• OS X 10.9 Mavericks-2013.
• OS X 10.8 Mountain Lion- 2012.
• OS X 10.7 Lion- 2011.

What is Safeboot mode?

Safe Mode allows you to safely power on your computer in the event that there is a system issue, and can help resolve various problems with your Mac. This document will explain the various reasons you may wish to boot your Apple computer into safe mode, as well as the steps on how to do so.

What is command R on Mac?

Command-R restores the latest macOS that was installed on your Mac without upgrading to a later version. Option-Command-R upgrades to the latest macOS that is compatible with your Mac. Shift-Option-Command-R restores the macOS that came with your Mac or the version closest to it that is still available.

What is the Command and R keys on a Mac?

Command (⌘)-R: Start up from the built-in macOS Recovery system. Or use Option-Command-R or Shift-Option-Command-R to start up from macOS Recovery over the Internet. macOS Recovery installs different versions of macOS, depending on the key combination you use while starting up.

How do I choose my operating system on startup?

To Choose Default OS in System Configuration (msconfig)

1. Press the Win + R keys to open the Run dialog, type msconfig into Run, and click/tap on OK to open System Configuration.
2. Click/tap on the Boot tab, select the OS (ex: Windows 10) you want as the "default OS", click/tap on Set as default, and click/tap on OK. (

Can I boot my iMac from an external SSD?

A more cost effective and less intrusive method is to use an external solid state drive instead, like the Samsung T5. Booting from a solid state drive like the Samsung T5 should give you a boost in performance, especially if you are running an older iMac with a 5,400 RPM hard drive.

How do you clean your startup disk on a Mac?

To remove app cache files and clean up a startup disk, follow these steps:

1. Navigate to Finder > Go > Go to Folder.
2. Type in ~/Library/Caches.
3. Go into each folder (or just the ones taking up the most space) and delete the files inside.
4. Now do the same for /Library/Caches (without the ~)

Which Mac operating system is best?

The best Mac OS version is the one that your Mac is eligible to upgrade to. In 2021 it is macOS Big Sur. However, for users that need to run 32-bit apps on Mac, the best macOS is Mojave. Also, older Macs would benefit if upgraded at least to macOS Sierra for which Apple still releases security patches.

What is macOS written in?

Is Catalina better than Mojave?

Mojave is still the best as Catalina drops support for 32-bit apps, meaning you will no longer be able to run legacy apps and drivers for legacy printers and external hardware as well as a useful application like Wine.