He is said to have seen the suffering of the world one day in three forms: an old man, an invalid, a funeral procession. He was deeply troubled and, aware of the vanity of all pleasure, he left home in pursuit of Knowledge.
This 'enlightenment' could be expressed in this core of beliefs: there is no need for God; the reason for all suffering is desire; to extinguish desire is the supreme goal. One progresses through reincarnation and accumulation of good Karma until the attainment of Nirvana - a state of non-existence (impossible to explain fully, but best illustrated by the blowing out of a candle).
To attain this one must first realise the four noble truths:-
The noble eightfold path is comprised right knowledge, right attitude, right speech, right action, right living, right effort, right mindfulness, right composure. The first two fall under the heading 'wisdom', the next three under 'ethics', and the rest under 'mental discipline'.
Dharma is the way to tread the eightfold path - a personal dynamism that gives inner power and quality to life. The Buddha spoke of Dharma as lovely and taught that the religious life consists in friendship with 'what is lovely'. This was the prior condition for the sustained practice of the noble eightfold path.
Buddhists follow five precepts, which prohibit killing, stealing, illicit sexual relations, gossiping, drugs or alcohol.
The Buddha is revered as a saintly example, but not divine. What looks like worship of idols is in reality a 'paying of respects' to his memory. Meditation in Buddhism is important. It can focus on breathing (half-way between voluntary and involuntary action - good for self-control) and ones own attitudes where one focuses on divesting oneself of craving and sense of self.
Scriptures aid meditation: the Tripitaka (triple basket) is the canon of tradition and teachings of Buddha.
Both streams are commonly mixed in actual practice with animism (spirit world) and animistic rites (Thailand's Buddhist homes all have spirit houses).