Giving a nod to the timetable that underlies its very existence, Google's near-daily Doodle on Tuesday celebrated the 434th anniversary of the Gregorian calendar.
The Gregorian calendar, if you didn't know, is the official name of the calendar as we know and love it today. It was introduced by Pope Gregory XIII during the Renaissance, replacing the Julian calendar that had been around since the days of Julius Caesar over 15 centuries earlier. The Julian calendar, as it turned out, was marginally short of the actual solar year -- measured by how long it takes the Earth to move around the sun -- and so important dates like Easter were drifting later in the year.
The Gregorian calendar was introduced on October 4, 1582, and is today widely used around the globe.
Google's Doodles have celebrated many events, birthdays and milestones all over the world, from national holidays, to birthdays of public figures, and even created a wonderful animated video for Freddy Mercury's 65th birthday.