Farming has just started in 8,000 BCE and people are learning how to farm by laying seeds in the ground. So far it seems to be working, although the average life expectancy is dropping.
In 6,000 BCE farming has become more advanced and people start to develop tools. This helps them to make a surplus, which they never had before.
Three things happen in 5,500 BCE. Population increases drastically, and because of the surplus, people start to stop farming and start specializing in other jobs, and people start to build permanent homes.
Many buildings have been created to house all the people from the population growth. This means cities start to pop up.
People create symbols to represent the words we have today. They used these to keep track of the things they have. This also leads them to develop laws to keep the people of cities in line.
This leads people to develop entire civilizations, which eventually leads to the modern society we have today!