"The Galactic Essential: Celebrating the Towel's Indispensable
 Role in Interstellar Hitchhiking"
A towel, it has been said, 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; lie on it on the brilliant marble-sanded beaches
 of Santraginus V, inhaling the heady sea vapors; 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 mind-bogglingly stupid animal, it assumes that if
 you can't see it, it can't see you   daft as a brush, but very, very
 ravenous); and, of course, 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.
More importantly, a towel has immense psychological value. For some
 reason, if a strag (strag: non-hitchhiker) discovers that a hitchhiker
 has his towel with him, he will automatically assume that he is also
 in possession of a toothbrush, face flannel, soap, tin of biscuits,
 flask, compass, map, ball of string, gnat spray, wet weather gear,
 space suit, etc., etc. Furthermore, the strag will then happily lend
 the hitchhiker any of these or a dozen other items that the hitchhiker
 might accidentally have "lost." What the strag fails to
 realize is that a man who can hitch the length and breadth of the
 galaxy, rough it, slum it, struggle against terrible odds, win
 through, and still knows where his towel is, is clearly a man to be
 reckoned with.
In many of the more relaxed civilizations on the Outer Eastern Rim of
 the Galaxy, the towel has taken on such a significant role that it has
 become an important part of local customs and etiquette. In some parts
 of the galaxy, it is traditional to present a newly arrived guest with
 a towel, as a sign of the host's intention to provide for the guest's
 needs and to ensure that the guest feels welcome. Such practices
 deeply emphasize the cultural significance of towels beyond their mere
 utilitarian value.
In light of its undeniable utility and widespread recognition, the
 Towel Day has been established in honor of the late Douglas Adams,
 author of the "Hitchhiker's Guide to the Galaxy" series.
 Celebrated annually on May 25, enthusiasts prominently carry a towel
 with them throughout the day to demonstrate their love and
 appreciation for the books and the invaluable piece of advice
 contained within its pages: "Always know where your towel
 is."
Therefore, to all you hitchhikers embarking on your travels across the
 universe, remember the advice passed down through the cosmic ages: a
 towel is the most important item a hitchhiker can have.