Working with Saved variables is great for smaller and less sensitive data. You may wish to have something which gives you more control. Perhaps you want to be able to save data to a custom path. One thing is certain, that if you need to encrypt your data from easily being modified by a third party, then this is for you.
If you are unfamiliar with Binary Encryption, it works by scrambling the data, obfuscating what is actually there. If you opened a file saved using binary, you would see a series of symbols and random looking text. The encryptor knows how to get back the data, but it can not be directly modified without first reversing the encryption files back into the data type. It is never truely possible to be unhackable, but it will provide much better protection then a stricly text based solution. If you need a modifiable solution, you are best using something like JSON.