Since its move to online purchasing and distribution of its operating system software, Apple has no longer included gray recovery DVDs with its Mac systems. Instead, if you wish to reinstall OS X ...

Turn a spare USB Flash drive into an emergency Mac OS X recovery boot disk in case you need to fix your Mac.

Install OS X either through Internet Recovery (for OS X 10.7 or later), a USB recovery disk or the original install discs if you have OS X 10.6 or earlier.

How to make your own bootable OS X 10.10 Yosemite USB install drive Setting up lots of Macs? Want an offline installer? Here's how to roll your own.

Once that’s done, you’ll have a bootable USB flash drive that fits in your pocket and can handle system recovery, OS installation, and even basic Web browsing in a pinch.

Tip: Create a Windows 8 recovery drive Unlike earlier versions of Windows, 8 and 8.1 include simple, quick tools to create USB system-recovery drives.

Learn how to create & use a Recovery Drive for Surface devices by following this tutorial. You will have to use the Create a recovery drive feature.