The story of Buddhism began in 520 BC when Siddhartha Gautama, a prince in Lumbini, was unhappy with his royal life. From suffering, he wanted to see why other people and himself did and what the purpose of suffering was for.
To find the reasoning behind suffering and an explanation of life and happiness, Gautama went on a journey. This journey lasted him 6 years of meditation and exploring different religions.
From much meditation, Siddhartha had found what he was looking for: the key to human happiness. Through his meditation and discovery of the truth about life, the now called Buddha was enlightened (when a Buddhist reaches Nirvana and stops being reborn--also explained through reincarnation)
After his discovery, he spent the rest of his life wandering Asia to preach his newly found religion. Some of his teachings included the Four Noble Truths, the eightfold path enlightenment (nirvana), the Five Precepts, and more to lead a positive, happy life.
As part of his teachings, the Buddha discussed these Four noble truths of Buddhism, which explains life suffering. 1.) Life is suffering and you can't live without death, frustration, etc. 2.) Suffering is caused by craving and aversion 3.) Suffering can be overcome where true happiness is attained 4.) The eightfold path leads to the end of all suffering
The Four Noble Truths
The Buddha also expressed the five precepts, the moral code of Buddhism, in his teachings. 1.) do not take the life of anything living 2.) do not take anything not freely given 3.)abstain from sensual overindulgence 4.) Refrain from untrue speech 5.) Avoid intoxication (do not lose mindfulness)