The Islamic Calendar

The Islamic calendar is different from the Gregorian calendar.  The Islamic calendar is based on the lunar year, unlike the Gregorian calendar, which is based on the solar year -- the length of time it takes for the earth to revolve around the sun.

The lunar year consists of twelve months, each consisting of 29 to 30 days.  Each month begins and ends with the new moon.

Since there are fewer days in the lunar year, the lunar calendar is unrelated to the progression of the seasons.  For example, the month of Ramadan could occur in the winter of one year and fifteen years later occur in the summer.  This occurs because the calendar progresses by ten or eleven days each year.  Therefore, every 33 lunar years is equivalent to 32 solar years.

The Islamic calendar has been in existence since the seventh century.  It was established during the rule of Caliph Umar ibn al-Khattab, the second caliph after the death of the Prophet Muhammad.  The starting point of the calendar is July 16, 622 A.D., which is the date of the Hijrah (migration) of the Prophet Muhammad from Makkah to Madinah.

The Muslim months are: