The primary sector of the economy extracts or harvests products from the earth. The primary sector includes the production of raw material and basic foods. Activities associated with the primary sector include agriculture (both subsistence and commercial), mining, forestry, farming, grazing, hunting and gathering, fishing, and quarrying. The packaging and processing of the raw material associated with this sector is also considered to be part of this sector.
In developed and developing countries, a decreasing proportion of workers are involved in the primary sector. About 3% of the U.S. labor force is engaged in primary sector activity today, while more than two-thirds of the labor force were primary sector workers in the mid-nineteenth century.
Though it is labour intensive and does not contribute directly to the economy but it provides a base to the secondary and tertiary sector to grow.