Buddha Dharma Education Association
Buddha Net: The Chinese Canon
A long essay on the Tripitaka, the Chinese Mahayana scriptures. Discusses the various parts, their history, and their importance.
Buddha Dharma Education Association
Buddha Net: What Are the Three Refuges
BuddhaNet offers a short explanation of the Three Refuges (a.k.a. the Three Gems) of Buddhism, the Buddha, the Dhamma (Dharma), and the Sangha.
Buddha Dharma Education Association
Buddha Net: Buddha, Dhamma, Sangha
BuddhaNet.net offers a long discussion of what the Three Gems are and what it means to take refuge in them.
Buddha Dharma Education Association
Buddha Net: Dhammapada Instructions to Monks [Pdf]
Excerpts from the Dhammapada, a collection of sayings attributed to the Buddha, which describe how a Buddhist monk ought to conduct himself.
Other
Access to Insight: The Threefold Refuge
Selections from the Pali Canon about the Three Refuges (Three Gems).