Mad Hatter Day celebrates the Mad Hatter, from Alice In Wonderland. The original picture of the Mad Hatter by John Tenniel in Alice’s Adventures In Wonderland (more commonly known as Alice In Wonderland, by Lewis Caroll) always depicts him wearing a hat, bearing the note “In This Style 10/6″. Although we know this is really an order from the time the picture was drawn to mean a hat in that style cost 10 Shillings and Sixpence, we take this as inspiration to act in the style of the Mad Hatter on 10/6 (In the UK this would point to the tenth of June, but as the day was founded in America it is the 6th of October).

History

In 1986 some computer-folk in Boulder, CO celebrated a general day of silliness, inspired by the drawings of the Mad Hatter by John Tenniel in Alice In Wonderland. It was announced that year on computer networks, becoming more popular as people realised its value – some people did less damage by celebrating silliness than if they had done their jobs.

In 1988 it was first recognised as a official holiday and recieved its first national press coverage.

Observances

As well as being a day to celebrate silliness, recent celebrations include looking for something completely sane in your everyday life. How sensible is it to tie a noose around your neck every day to look important at work?

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All details taken directly from provider content at http://www.daysoftheyear.com/days/mad-hatter-day/