# Intradependent encodings can be compressed

Given an encoding scheme $$E$$ which gives an Intradependent encoding of a message $$m,$$ we can in principle design a more efficient coding $$E^\prime$$ that gives a shorter encoding of $$m.$$ For example, $$E$$ encodes 8-letter English words as a series of letters, $$m$$ is aardvark, then $$E(m)$$ is intradependent (because you already know what the message is by the time you’ve seen “aardv”), so you can define an alternative encoding $$E^\prime$$ which encodes “aardvark” as just “aardv”, thereby saving three letters.

The practice of taking an intradependent encoding and finding a more efficient one is known as compression.