An old (criminal) teacher once told me, "If a lock can be made to keep people out, someone can get in. If a lock can be made to keep people in, someone can get out."
The Nazi warriors, during WWII, thought they had a breakproof encryption method for safe communications. British cryptologists decrypted a vast number of messages enciphered on the machine known today as Enigma. The intelligence gleaned from this source, codenamed "Ultra" by the British, was a substantial aid to the Allied war effort.
Then came computers with muscle. Today, encryption software such as VeraCrypt are practically unbreakable. Note that I said "practically". All... let me repeat that... ALL cyphers are theoretically breakable. It's just a matter of time to do it. VeraCrypt is theoretically breakable but, with the fastest of computers today, a thoroughly encrypted file would probably take several millions of years to break the cypher. Keeping that in mind, that very same file could be decrypted in seconds if someone HAD THE KEY. Watching someone type on their keyboard will easily reveal a key to such an encrypted file. There are many different ways to accomplish that.
Codes, however, are theoretically unbreakable. For example, what do I mean when I say, "Dodgson!" You have some ideas of what that could mean considering that you are reading this here, but... what if I meant, "There's a Panzer Tiger tank here!" or "I'm coming home next week."
If you didn't know Simplified Chinese characters, how could you figure out what, "现代软件易于翻译" means? A meeting tonight? Run, the cops are after us?
Then there is steganography, the practice of concealing a file, message, image, or video within another file, message, image, or video. To demonstrate this concept, I've made it very easy to see in the paragraph above that begins with, "Codes, however..." Look at all the lower case letters "y". When you first read the paragraph, did you see that all of the lower case letters "y" were in italics? There are three of them. Of course, there is no real message in three lower case letters, but it should demonstrate just how a message can be sent relatively safely. (If you are truly obsessed with solving a code puzzle, you could even check the "off" colors of all of the characters in this post for being CLOSE to black... say, dark blue. Hard to see on some computer monitors but, a quick look at the webpage source should reveal if I used "off" color in any of my text or not. Maybe I did, maybe I didn't. It will take you some time to check, eh?)
There are all sorts of tricks to catch obfuscations. "If a lock can be made to keep people out, someone can get in. If a lock can be made to keep people in, someone can get out."