Following is the Defination of Zakat:
“Transferring ownership of an amount of material wealth specified by the Lawgiver to a poor Muslim who is not Hashimi nor their client, without material benefit returning to the giver in any way, for the sake of Allah Most High.” [Tumurtashi, Tanwir al-Absar]
There are many important points understood in this definition:
1. It is a condition that there be a transferring of ownership. (Simply put: your zakat has to be given). As such, it is not valid to forgive a debt someone owes you as zakat.
2. Zakat has to be given to the poor and needy. It is not valid to give zakat for projects, mosques, and virtuous activity, unless the zakat itself will be given to the poor and needy.
3. Zakat must be given to a Muslim. Unlike charity, it is not valid to give zakat to a non-Muslim.
4. Zakat cannot normally be given to Hashimis (those from the family of the Prophet (Allah bless him and give him peace)).
5. The giver cannot materially benefit from giving their zakat. As such, one cannot give zakat to one’s parents, children, or spouse, because benefits between these people are shared.
[Ibn Abidin and Haskafi, Radd al-Muhtar `ala al-Durr al-Mukhtar 2.2-4; Ibn al-Humam and Marghinani, Fath al-Qadir Sharh al-Hidaya]