Millions of Muslims all around the world will be celebrating Eid al-Fitr this week to mark the end of Ramadan.
Eid al-Fitr means: 'festival of the breaking of the fast' and it is one of the biggest celebrations in the Islamic year.
The date Eid falls on is decided by the cycle of the moon and should fall around Tuesday this week.
The month of Ramadan is a time for spiritual reflection, prayer, doing good deeds and spending time with family and friends.
During Ramadan, Muslims avoid eating from dawn until sunset for about a month.
On the day of Eid al-Fitr, Ramadan is over and Muslims often celebrate by praying, giving gifts and having a big feast with family and friends.
Eid celebrations begin when a new crescent moon appears in the evening sky, which means that Eid can be on a different day each year.