Once there was a guy named Siddhartha and he lived in a palace and was home-schooled by a Tutor. The tutor had a son and after their lessons were done they would go play in the fields. Years passed and one night the Tutor's son had to leave to go home. "Why are you leaving" asked Siddhartha. "I have to go home for dinner" he said. "Well can I come" said Siddhartha. "Yes you can come" said the Tutor's son.
On their way Siddhartha saw a dead, sick, and old, man and wondered if that would ever happen to him. After dinner at his friends house he was shocked from fear but still went on to have a family years later, and experienced joy hearing the first laughs of his baby. But he also knew that there was hard time to go through in life so he ventured to a mountain to find the point of life. He stayed in a cave for 6 months starving himself and praying to the gods.
One day a little girl brought him a bowl of rice and he thought to himself, man this is good, why am I starving myself. So he headed back home and on his way he found a big tree to sit under and he thought about life sitting there for a day. And finally he was enlightened, he new the meaning of life and once he knew it he started teaching it to other people and called it dharma. Once people started to learn about this, it was spread and kept spreading, and that's how it spread.