The Neolithic Revolution was the period of history where the Nomads - a group apart of the Homo Erectus period - started appearing. These people are the first to start walking upright. They spent a lot of their time moving around trying to hunt for food.
The environment around them was mostly wood and forrest and they only had stone tools to clear for farm fields. They used their new knowledge of fire to burn the wood to the ground. The plan was called slash-and-burn where they would chop the trees then burn them.
They learned to farm because hunting was not a steady supply of food. Agriculture became a big part of their every day lives. Now that they had different ways of food they needed specialized workers to focus on just one job and then they become better at it.
They would place their farm fields near a body of water like a lake or river. They started irrigating the land by changing where the water was going. By doing this the soil became richer and was better to farm on.
They also learned how to domesticate animal such as dogs, horses, goats and pigs. They would keep them in a closed area and would take care of them so when they need meat they can use those animals. This was a better source of meat then what the hunter-gatherers were doing.
By learning these new survival jobs the Nomads started to grow in village size and became advanced cities. Each cities started to have their own unique culture and how they lived their lives. These cities started popping up around in a lot of river-valley land.