A month of fasting to remember when the prophet Muhammed was given the Koran - the sacred book of Islam.
Traditions
Muslims fast from dawn until dusk for 30 days - that means eating nothing while it is daylight (young children, pregnant women, the sick and travellers don't have to fast).
At the end of the fast people dress in their best clothes and go to the mosque to pray.
Special celebration meals are served. Everyone has a holiday and big family groups get together.
Children are given sweets, presents and often new clothes.
When?
Ninth month of the Muslim calendar.
Because Islam uses a lunar calendar, the month of Ramadan comes around 11 days earlier each year, so it isn't a fixed date in the Western calendar.
The festival to celebrate the end of Ramadan, and fasting, is called Eid al-Fitr.