Around 10,000 B.C., man discovered that by sowing the grain, which he had gathered from the jungle, in the ground he could produce completely new plants to meet his food requirements. This was the beginning of the agriculture.
Slowly, he learnt that if the soil was loosened before sowing, seeds had a better chance of germinating and growing into healthy plants. This must have led to the invention of plough. Later, in order to meet the increased energy demands he started domesticating certain animals. These domestic animals also provide him food, such as milk and meat.
At this stage, nomadic life of man came to an end. From being a wondering food gatherer he becomes a food producer. Many stable settlements came around the farms. These settlements multiplied with time. In order to meet his growing needs, man selected the right species of plants and animals, and tried to improve the various agricultural practices. Continuous improvement in various agricultural practices gave rise to the great irrigation civilizations of the fertile crescent and the Indus Valley.
Modern methods of agriculture are almost same as those employed by the Indus Valley people more than 5000years ago. However, the modern agriculture is carried out on a much larger scale and in more systematic way.
However, at the same time our population has also increased at a very fast rate. Our population increases by approximately 20 millions every year. As a result, in spite of the tremendous increase in the food production we constantly fall short of food requirements.