For those of you who have never heard of The Hitchhiker's Guide to the Galaxy.... SHAME ON YOU. But no worries, we shall educate you.
HHGG is a series of novels about Arthur Dent and his best friend Ford Prefect (who turns out to be an alien). Furthermore, he is the author of the HHGG. Basic story is: Earth goes BOOM, Arthur and Ford get picked up by Vogon ship, there is poetry, they get spaced, they are picked up again by Trillian (another human) and Zaphod Beeblebrox (alien) not to mention Marvin (<3) and ... well... THINGS happen.
So what's the deal with the towel?
A towel, it says, is about the most massively useful thing an interstellar hitchhiker 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 vapors; you can sleep under it beneath the stars which shine so redly on the desert world of Kakrafoon; use it to sail a miniraft 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 avoid the gaze of the Ravenous Bugblatter Beast of Traal (such a mind-bogglingly stupid animal, it assumes that if you can't see it, it can't see you); 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.
- Douglas Adams (The Hitchhiker's Guide to the Galaxy)
Ok... so? What's the big deal?
In 2001, Douglas Adams died way too soon. So a couple of fans started this Towel Day to commemorate him. Several fans around the world have joined in this annual event.
So Towel Day is May 25th. The only thing you have to do is to wear your towel with you... all day. I celebrate this joyous event every year, so I hope everyone else decides to join in as well