If on a bad day, your Mac can not boot into Mac OS X usual or you just want a different method for booting Mac. Apple offers users a number of Mac keyboard shortcuts for Booting, all you need to do is totally powered off, press the power button and hold the following keys

• Hold down the “C“: Boot from USB, DVD.

• Hold down the “X“: launch directly into Mac OS X Startup Disk ignored.

• Hold down the “N“: launch from NetBoot server is a server system – workstation. You can install or boot OS X via the network using OS X Server services.

• Hold down the “T“: Target Disk Mode Startup Mode. This mode allows Mac boot from FireWire or Thunderbolt. or connect with one another Mac as an external drive.

• Hold down the “D“: launch the Apple hardware test – test mode for Mac hardware failure.

• Hold down the “Option“: start the boot menu – allows you to select the boot partition.

• Hold down the “Shift“: launch safemode for Mac.

• Hold down the “Command + R“: launch the Recovery HD partition, allowing you to restore your operating system for the Mac, or use a variety of tools to fix Mac.

• Hold down the “Command + Option + R“: launch on Apple Server, need to have an internet connection, a program including Disk Utility has the ability to download and install OS X, or restore from Time Machine Backup.

• Hold down the “Command + V“: launch in Verbose mode – mode display of what happens during boot Mac.

• Hold down the “Command + S“: launch into Single-User mode – is a special mode to fix the hard drive.

• Holding down the “Command + Option + R + P“: reset PRAM – press and hold the key combination until the Mac startup sound emitted 2 times. Liberating effect PRAM put on display the default configuration setting, time and date, time zone, speaker volume, DVD setting, Region.

Hope the Mac Keyboard Shortcuts useful for you!