Entropy doesn't have to be confusing

Entropy is a measure of chaos.  This is technically accurate, but a poor descriptor.

Entropy is a measure of disorder.  This is better, but not quite there yet for the average person.

Entropy is a measure of ordinariness, or averageness.  That’s the ticket!

Any situation where you could scatter items around like a messy toddler having a particularly energetic day is one of high entropy.  If the toys were scattered about the play room in a different manner, would you even notice?

A low entropy situation is what you get after the toddler is finally asleep, and Mom finally has time to tidy all the toys back into the toybox.  The entropy has been reduced to the order of the toys inside the box.

White noise has high entropy.  Pink noise has less.  A pure tone has very low entropy.  Note that it still has some.  After all, it doesn’t have to be that particular frequency.  There are many others it could have been.

If Jackson Pollock made a thousand of his infamous paintings, they’d all look very similar to each other.  They are high entropy.  But you can instantly tell each Rembrandt from all the others.  They are low entropy.

Entropy is inversely related to how predictable a collection of things are.  In the messy play room, if you pick one toy, you have no idea where a similar toy might lie.  It might be under this one.  It might be way over in the corner.  There’s no way to know without searching for it, and that might take a while.  In the tidied up play room, if you pick a toy, a similar one will probably be close by.  Searching for it will probably take very little time at all.  But the act of searching for it may temporarily increase the entropy, as you move some toys around to look underneath them.  You might even have to take some out of the box until you find the toy in question, which the child apparently can’t sleep without today.  No, not that one.  This one, which is 99% identical, except for the one floppy ear.

A low entropy message is one in which you can pretty much guess what’s going to be said next.  A high entropy one communicates almost no information, because it doesn’t make any sense.  It’s a jumble of unrelated syllables.  A properly encrypted message has a very high entropy.  A properly decrypted message should have a very low entropy, unless the original sender was drunk.

Low entropy:  abcdefghijklmnopqrstuvwxyz

Higher entropy:  qwertyuiopasdfghjklzxcvbnm

High entropy:  asdfqrtmbnxcvoiuasdgfjhjew

Very high entropy: dlkjlownvWSJfvh3DFGJU4Tgdy654er@#^Hhfds4f