What periods have historians divided time into?

For the convenience of studying historical events, historians have divided history into five periods. The first of them is the least studied and oldest. Primitiveness is the origin of history. About 40 thousand years ago, people just began to form. The next stage was Antiquity. It lasted from the 4th century BC. until the 5th century. At this time, there was a flourishing of slave relations and military despotism. The next period is the Middle Ages. The modern era lasted from the 16th to the 19th century. The frames differ depending on the country. The newest history began in the 20th century.