To look this up, go to the Finder's Go menu, choose the Computer option, and then right-click your hard drive (called Macintosh HD by default) and get information on it. Purchase or obtain a USB or Firewire hard drive that is at least the size of your internal hard drive (or at the very minimum the same size as the data on your drive). While you can use Time Machine to back up to network devices such as Apple's Time Capsule, and OS X Server, or other network devices, if you are just starting to use Time Machine then the basics of setting up a quick backup can be done in a simple two-step process:

Getting information on your hard drive will show its overall capacity and the amount of space being used. In OS X Apple's Time Machine feature offers a convenient backup option, which once activated will automatically keep hourly backups of your entire system, including the operating system and user accounts so you can easily restore individual files or your whole OS X installation, if needed. If you do not already have a backup plan for your Mac, then perhaps in light of World Backup Day you might take a look at making one. There are many ways to back up your files, including using external hard disks, Internet-based storage, or CDs and DVDs, so the approaches you choose for backing up are up to you however, whichever route you choose, one important thing about backing up is that you do so regularly. As anyone who regularly uses computers ought to know, backing up is a vital step for the safety of your files, especially when troubleshooting problems with your system where you may update software, change configurations, or need to reinstall the OS. Tomorrow is World Backup Day, which is an effort to spread the word about the importance of backing up your computer.

Setup time machine on mac