Zakat is the third pillar of Islam that requires Muslims to donate a portion of their wealth to charity. It is an obligatory annual donation of 2.5% paid by Muslims with wealth above a minimum threshold to help the poor and needy. Historically, zakat funds were used to build public services like schools, fountains, inns, hospitals, and orphanages to benefit the community. Today, zakat continues to support charities that provide food, shelter, healthcare and clothing to those in need.