Amanda Unvarnished

Yeah that sounds complicated.

Please keep manual for future confusing. Seriously though I hope your wife's experience with the new machine doesn't end up being too complicated and that she gets good coffee.

The Muslim calendar is entirely lunar, which is why Ramadan, for example, shifts throughout the year.

No, Easter works out for Catholics and Protestants as the first Sunday after the Ecclesiastical full moon that occurs after March 21, and for the Orthodox, Easter is calculated the same way, but it has an added rule that it must fall after Passover. Passover and other Jewish observances are calculated from astronomical new moon and usually occur on astronomical full moon. The Western churches fix the vernal equinox on March 21, when astronomically it can occur on either 21 or 22 March.

So it has more years, but only because the Gregorian calendar, which is what's used in the West, is calculated from the traditional birth of Jesus, (Ano Domini, or the Year of Our Lord in Christian reckoning).

The Hebrew calendar is lunisolar. What that means in practice is that Passover can't fall in any other time of year than spring, which then anchors the rest of the festivals and other calendrical observances. The Hebrew calendar dates from the calculated date of the creation of the world, which corresponds to sunset on October 6 3761 BCE when you extend the traditional Julian calendar back in time before its implementation in 45 BCE.