Buddhism is a nontheistic religion that surrounds a bunch of traditions, beliefs and practices largely based on teachings attributed to Siddhartha Gautama, who is commonly known as Buddha, which means "the awakened one".
Through meditation and study, buddha achieved an informed state of being that marked the end of attachments and ultimately, upon his death, free from the cycle of rebirth.
The Buddha's teachings are often summarized in the Four Noble Truths, which forms the basis of the first sermon he delivered after attaining enlightenment, and the Eightfold trail, which provides a basic way for how to live in the world.