How do I Encrypt sensitive information?

If you just want to encrypt a little information, you could create an encrypted disk image using Applications -> Utilities -> Disk Utility -> File -> New -> Blank Image -> Encryption -> 256 AES

Mount the disk image when you want to access the sensitive information, eject (unmount) the disk image when you want it to be locked up.

Hello angelbergth,

Turn on FileVault in System Preferences > Security & Privacy > FileVault