This article briefly describes cryptography.. I wasn't quite sure if it is more understandable. Just like some people said.., if you are able to understand something then you can understand.. else you can't ..
In symmetric encryption, industry uses only AES and Stream Cipher such as ChaCha20 or Salsa20. GSM,DES and RC was deprecated.
We should not understand a topic based on fixing a subtopic.. or limiting on using certain information to understand.. We have to look at the topic as a whole..
Hope you guys enjoy this article.
Thanks for your interest.