The three jewels of Buddhism
The Buddha, the fully enlightened one.
The Dharma, the teachings expounded by the Buddha.
The Sangha, the monastic order of Buddhism that practice the Dharma.
This forms the basis of how to escape the cycles of life and suffering, by taking refuge in these when you need to find clarity of thought and to learn from the suffering of life.
In some schools the three jewels are known as the three places of refuge or the Triple Gems.