What is the maximum theoretically possible compression rate?

Question

This is a theoretical question, so expect that many details here are not computable in practice or even in theory.

Let\'s say I have a string s that I w

Answer 1

Claude Shannon estimated the information density of the English language to be somewhere between 0.6 and 1.3 bits per character in his 1951 paper Prediction and Entropy of Printed English (PDF, 1.6 MB. Bell Sys. Tech. J (3) p. 50-64).