Is Zakat obligatory on a monthly salary, and what is its amount? Is it permissible to give it as a perpetual charity by photographing supplications and distributing them?

The ruling on Zakat (definition) for salaries has been previously explained. Whoever is eligible for Zakat must disburse it to its eight categories, as mentioned in the verse: "Indeed, [prescribed] charities are only for the poor and the needy, and those employed to collect [them], and those whose hearts are to be reconciled, and for [freeing] captives, and for those in debt, and for the cause of Allah, and for the wayfarer - an obligation [imposed] by Allah. And Allah is Knowing and Wise."