8 Use FileVault
Depending on your circumstances, you may need to protect the files and data on your Mac with more than just a root password. Apple knows this — and that’s why it offers a powerful yet completely free security feature that’s baked into macOS.
That feature is called FileVault. It’s full-disk encryption for your Mac. While you can certainly delve into the technicalities of it, the end result is that it will be much, much harder for attackers to try and access your data. You can enable it in System Preferences > Security & Privacy.
Note: If you opt to use FileVault, make sure you set a secure password and recovery key — and DO NOT lose them. If you lose either one, you will completely lose access to your data.