Are you changing your computer and getting rid of your old Mac? But how to completely erase all your personal information on the drive? One way is to smash it with a hammer, or drop from a high building onto concrete.
There are few far less destructive ways to make sure all your private data is gone for good.
The first thing is to make sure you have a backup
Before erasing all your data make sure that you all important data you need is moved to a safer place. One way to do this is using OS built-in Time Machine backup software.
To make sure your data is safe no matter what happens it is better to make both local and cloud backup.
The key is OS X Recovery feature – a special part of Mac operating system since OS X 10.7 ”Lion”.
How to erase a Mac internal hard disk?
1. Firstly, make sure your Mac is turned off
2. Press the power button
3. Immediately hold down the command and R keys
3. Now wait until the Apple logo appears
4. Then Select “Disk Utility” from the OS X Utilities list and click on Continue
5. Now on the sidebar click on the hard disk you want to erase
6. Click Erase button
7. Now Click the Security Options button
8. The Security Options window has a slider that enables you to choose how fully you want to erase your internal hard drive. You need to choose from four notches on Security Options slider. The “Fastest” is a quick but insecure way to erase your drive because data could potentially be rebuilt using a file recovery software. Move that slider to the right and you will see much more secure erasing option. When you use Disk Utility`s most secure erase level, it will erase all the information used to access the files on your hard disk and then write zeroes across the hard drive surface seven times. That will help to remove any traces of what was on the hard drive. This feature conforms to the DOD 5220.22-M specification.
9. After selecting the level of secure erasing you can Click the OK button to continue
10. Now Click Erase button to begin process. Notice that the more secure level you choose, the longer it will take to erase data. With the most secure method it can take up to few hours.
Once the process will finish you hard drive will be clean from all data and ready to be used again. Now you can install a fresh version of OS X or donate it to a local charity. Of course, you can still smash it with a hammer or drill a hole in it.