On Towel Day...

The Hitchhiker’s Guide to the Galaxy has a few things to say on the subject of towels.
A towel, it says, is about the most massively useful thing an interstellar hitch hiker can have. Partly it has great practical value — you can wrap it around you for warmth as you bound across the cold moons of Jaglan Beta; you can lie on it on the brilliant marble‐sanded beaches of Santraginus Ⅴ, inhaling the heady sea vapours; you can sleep under it beneath the stars which shine so redly on the desert world of Kakrafoon; use it to sail a mini raft down the slow heavy river Moth; wet it for use in hand‐to‐hand‐combat; wrap it round your head to ward off noxious fumes or to avoid the gaze of the Ravenous Bugblatter Beast of Traal (a mindbogglingly stupid animal, it assumes that if you can't see it, it can't see you — daft as a bush, but very ravenous); you can wave your towel in emergencies as a distress signal, and of course dry yourself off with it if it still seems to be clean enough.

One of the things Ford Prefect had always found hardest to understand about humans was their habit of continually stating and repeating the very very obvious, as in It's a nice day, or You're very tall, or Oh dear you seem to have fallen down a thirty-foot well, are you alright? At first Ford had formed a theory to account for this strange behaviour. If human beings don't keep exercising their lips, he thought, their mouths probably seize up. After a few months' consideration and observation he abandoned this theory in favour of a new one. If they don't keep on exercising their lips, he thought, their brains start working. After a while he abandoned this one as well as being obstructively cynical.