Gampopa was a highly influential Tibetan Buddhist master who lived in the 12th century. He is considered to be one of the main founders of the Kagyu school of Tibetan Buddhism, which emphasizes the practice of meditation and the transmission of teachings from teacher to student.

Gampopa's main contribution to Tibetan Buddhism was his integration of the Mahayana and Vajrayana traditions. He was originally a physician and lay practitioner, but after the death of his wife and child, he became a monk and devoted himself to the study and practice of Buddhism.

Gampopa studied under several renowned masters, including Milarepa, and eventually became a disciple of the great Tibetan master, Jetsun Milarepa. Under Milarepa's guidance, Gampopa achieved enlightenment and received the full transmission of the Kagyu lineage.

Gampopa's main contribution to Tibetan Buddhism was his synthesis of the Mahayana and Vajrayana teachings. He combined the teachings of the Mahayana, which focus on compassion and the path to enlightenment for the benefit of all beings, with the Vajrayana, which emphasizes the use of specific techniques and practices to achieve enlightenment in one lifetime.

Gampopa's teachings were based on the Four Dharmas of Gampopa, which are the Four Noble Truths, the Noble Eightfold Path, the Six Paramitas, and the Four Immeasurables. These teachings serve as a foundation for the practice of Tibetan Buddhism and are still widely studied and practiced today.

Another significant contribution of Gampopa was his emphasis on the importance of a qualified teacher-student relationship. He believed that having a trustworthy and knowledgeable teacher was essential for progress on the spiritual path. Gampopa also stressed the importance of devotion to one's teacher and the practice of guru yoga, which involves visualizing one's teacher as a Buddha and cultivating a deep connection with them.

Gampopa's teachings also had a significant impact on the development of Tibetan Buddhist monasticism. He established the first monastery of the Kagyu lineage, the Daklha Gampo Monastery, which became a model for other monasteries in Tibet.

In summary, Gampopa's main contribution to Tibetan Buddhism was his integration of the Mahayana and Vajrayana traditions, his emphasis on the importance of a qualified teacher-student relationship, and his establishment of the first Kagyu monastery. His teachings continue to inspire and guide practitioners on the path to enlightenment, making him a highly revered figure in Tibetan Buddhism.