Yawm al-Hajj (Hajj Day) refers to the Day of Arafat (9th Dhu al-Hijjah), the most essential day of the Hajj pilgrimage, though the term may broadly encompass the entire Hajj season. The Prophet Muhammad (peace be upon him) declared: "Hajj is Arafat" (Abu Dawud, Tirmidhi), meaning that standing at Arafat (Wuquf) is the essential rite without which Hajj is invalid. On this day, millions of pilgrims gather on the plain of Arafat from noon until sunset, engaged in supplication, repentance, and prayer, seeking Allah's boundless mercy. For Muslims not performing Hajj, fasting on this day is highly recommended, as the Prophet said: "Fasting on the Day of Arafat expiates the sins of the previous year and the coming year" (Muslim). Yawm al-Hajj embodies profound spiritual meanings: equality before Allah as pilgrims stand in simple white garments, unity of the global Ummah, humility and dependence on divine mercy, and anticipation of the Day of Judgment when all humanity will stand before their Creator. The Prophet delivered his farewell sermon on this day, establishing universal principles of human rights, justice, and equality. Yawm al-Hajj represents the climax of Islamic worship, where sincere devotion meets divine acceptance, and sins are forgiven, and souls are purified.