"All men .... are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness."
Natural rights have to do with rights every human being has, that cannot be taken away from them. They are not granted by an entity, so therefore they cannot and shouldn't be taken away from a person. Natural rights are considered freedoms that are automatic and in the past have been controlled to some extent by those in charge in countries or empires. So life, liberty and the pursuit of happiness stand for being in charge of one's own life, being free, and being able to do what makes one happy. At the time of the Declaration, this meant to be able to own property which was a new opportunity for many people in America.
