What is Zakat al-Fitr, what is its benefit, and why was its payment mandated before the Eid prayer?

Among the benefits of Zakat al-Fitr is that it purifies the fasting person from idle talk and obscenities, and it provides food for the needy. It is accepted if paid before the Eid prayer, and it becomes a charity like other charities if paid after the prayer. Most scholars are of the opinion that paying it before the Eid prayer is only a recommendation, and that it is valid until the end of the day of Fitr. However, delaying it beyond the day of Eid is Haram by consensus.