Guru Arjan Dev was the fifth Guru of Sikhism, serving from 1581 to 1606. He is known for compiling the Guru Granth Sahib, the holy scripture of Sikhism, which includes hymns from various saints and reflects the teachings of the previous Gurus. His efforts helped to establish a unified spiritual text for the Sikh community. Guru Arjan Dev also played a significant role in building the Golden Temple in Amritsar, which became a central place of worship for Sikhs. He emphasized the importance of equality, service, and devotion, promoting a message of peace and harmony among different faiths.