Tayammum is a ritual purification method in Islam that involves using clean soil or dust instead of water. It is performed when water is scarce, harmful, or unavailable for ablution. Tayammum allows Muslims to maintain their spiritual and physical cleanliness for prayer and other acts of worship. Tayammum is based on the Quranic verse 4:43 and the hadith of the Prophet Muhammad (peace be upon him). Tayammum has certain conditions, pillars, and invalidators that must be observed by the one who performs it.