The phrase “Don't Panic” can be seen in cities across the world to celebrate Towel Day.

May 25th marks the day that “The Hitchhiker's Guide to the Galaxy” author Douglas Adams passed away back in 2001. According to Adams and the book, a towel is the most useful thing a traveler can have, hence its symbolic role.

This year, Towel Day is being supported by the British publisher of Adams' books.

Implications - So don't be surprised to see these Don't Panic towels littered around town every year on May 25th. Instead, join in and celebrate one of the most prolific writers of this century by reading one of the "Hitchhiker's Guide to the Galaxy" novels or just flaunting your favorite towels around town.