Magical Encryption

Every so often, people of the planeverse wish to communicate with each other without any prying eyes or ears to evesdrop. Therefore they needed a safe and secure way to send, deliver and receive messages. Magical Encryption is the method which prevents unwanted, unauthorised access to messages in scrolls, books, or even the spoken word. In theory anything can be magically encrypted.

Decryption

There are those who wish to decypher these magical codes. These 'hackers' do all they can to gain access to these encrypted scrolls. Some do it for fun, but others do it as an occupation; or just to steal valuable information or items.

Usages

The key usage of this kind of magic, is to prevent access. For example, this can be in the form of a magical lock. However it can also be in the form of a scroll which may look like the writing is scrabbled, as it jumbled around the page; though the scroll could also look blank.
Governments use this technique to hide information which they wish the public, or worse their enemies, to know. Military plans and formations, spy and counter espionage information and even any personal information which could be used against those in power. This is so crucial to any kingdom or nation, that whole divisions are created to ensure the safety and security of government information.
Hubs of The Circuit also use encryption magic to hide their illicit deeds and acquirements too. However, they're mosy notorious of cracking secret codes than forming them.
Another use is how the Plane Barrier Probes are able to control what can and cannot phase between the plane and the Cosmic Sea. Probes apply Encryption Magic to the Plane Barrier, which can prevent unauthorised entry and exit between the plane and the Cosmic Sea.