Prophet Muhammad began receiving divine revelations from the Angel Gabriel in 610 CE while meditating in the Cave of Hira near Mecca. These revelations, which continued for 23 years, formed the basis of the Quran, Islam’s holy book. Facing persecution in Mecca, Muhammad and his followers migrated to the city of Yathrib (later renamed Medina) in 622 CE. This migration, known as the Hijra, marks the beginning of the Islamic calendar. In Medina, Muhammad established a new community based on Islamic principles. After Muhammad’s death in 632 CE, his successors, known as the Rashidun Caliphs, expanded the Muslim community through conquests and conversions. The early Muslim conquests spread Islam across the Arabian Peninsula, North Africa, and parts of the Byzantine and Sasanian Empires. The Umayyad Caliphate, established in 661 CE, continued the expansion of Islam, extending its reach to Spain in the west and the Indus River in the east. The Umayyad period saw significant cultural and scientific advancements, often referred to as the Islamic Golden Age. The Abbasid Caliphate overthrew the Umayyads in 750 CE and moved the capital to Baghdad. This period is marked by further cultural, scientific, and intellectual achievements, with Baghdad becoming a center of learning and innovation. Islam is one of the most famous and taught religions in the world, people from India, Seria, middle Europe mostly are either part of the religion or been near it for a while. The Ottoman Empire emerged in the late 13th century in Anatolia (modern-day Turkey) and expanded to become one of the most powerful states in the world. The Ottomans played a crucial role in the spread of Islam in Southeast Europe, the Middle East, and North Africa.