How did early humans obtain their food?

Early humans did not had the techniques that we possess in this era.They were also not so developed.The example can be seen in the way they obtained their food.They generally hunted animals.Later on they started distinguishing that which animal is poisonous and which is not!They also made tools by themselves.Earlier they didi not knew the techniques but with time they got to know!They also started searching for food products in the jungles.When some food products suited them they preffered it for a longer time.They hunted for deers,lions,tiger.