Zakat-ul-Fitr is a small amount that Muslims are obliged to pay as charity at the end of Ramadan. It is unanimously recognized by all schools of Islamic Law as a pious duty of every Muslim man or woman. The origin of the obligation can be dated to the month of Sha`ban in the second year of Hijrah. Ibn `Umar said: “Allah’s Messenger enjoined the payment of one Sa` of dates or one Sa` of barley as Zakat-ul-Fitr on every Muslim slave or free, male or female, young or old, and he ordered that it be paid before the people went out to offer the `Eid prayer.”
Zakat-ul-Fitr - Part 1
Zakat-ul-Fitr - Part 2
Sahih Bukhari: Volume 2, Book 25 - Zakat ul Fitr
All About Zakat Al-Fitr
Zakat-ul-Fitr: Rules and Significance
Can Zakat-ul-Fitr Be Paid in Cash?