Compression and error correction also go hand in hand: in compressed data every bit carries more information and therefore errors are more detrimental. This is one of the results that Shannon phrased exactly in terms of entropy.

My PhD supervisor had a beautiful example. Take an English message and ‘compress it’ by removing vowels. It’s still intelligible because English has redundancy:

rrrs cn mk mssgs nrdbl

Similarly, an uncompressed message with errors (swapped characters) is also intelligible because of the redundancy of English:

erwurs lan nake wesaagis unfeatable

But now we do both: we compress the message AND add errors. The result should be much harder (if not impossible) to read:

rwrs ln nk wssgs nftbl