After 27 years of sitting under the tree meditating, Siddhartha suddenly discovered the secret of suffering. Siddhartha realized that everyone suffers because of thier desires. Therefore to end one's suffering, you must end all of your desires. As quick as this, Siddhartha became enlightened and quickly ran to tell as many people as he could.
When Siddhartha began to tell people of his discovery, they immediatley realized that he had become enlightened and was all knowing. People began to call him Buddha which mean's "Enlightened One." Followers of Buddha were called Buddhists and they would meditate frequently in an attempt to become englightened like Buddha. Even in today's society, many Buddhists meditate in natural settings.