Note that in the Muslim calendar, a holiday begins on the sunset of
the previous day, so observing Muslims will celebrate Mawlid al-Nabi on
the sunset of the 3rd of February.
Although Mawlid al-Nabi is always on the same day of the Islamic
calendar, the date on the Gregorian calendar varies from year to year,
since the Gregorian calendar is a solar calendar and the Islamic
calendar is a lunar calendar. This difference means Mawlid al-Nabi
moves in the Gregorian calendar approximately 11 days every year. The
date of Mawlid al-Nabi may also vary from country to country depending
on whether the moon has been sighted or not.
The dates provided here are based on the dates adopted by the
Fiqh Council of North America
for the celebration of Mawlid al-Nabi.
The day is commemorated with recollections of Mohammad's life and significance.
Fundamentalist Muslims do not celebrate it.
-The above information is from:
http://www.infoplease.com/spot/islamicholidays.html
