Based on people’s proportion in a nation involved in an activity, the economy is divided into sectors according to the range of distance from the natural environment and is as follows:
Primary Sector involves in extracting or harvesting of natural products. Activities related to this sector include farming, hunting, mining, quarrying, fishing and agriculture. In U.S. about 3% of labour force is in this sector.
Secondary Sector engages in construction, processing and manufacturing of finished goods. Some examples of activities involved are automobile production, textile production, chemical and engineering industries, shipbuilding, breweries, energy utilities and metal working.
Tertiary Sector provides services to businesses and public. Some of the activities associated are transportation, entertainment, retail and wholesale sales, restaurant, tourism healthcare, banking and law. In developed and developing nations a large percentage of the population is in this sector for instance in U.S. more than 80% of labour force is in this sector.
Quaternary Sector consists of intellectual pursuits such as education, information technology and scientific research. It includes those involved in the highest level of decision-making in the economy or society, for example, representatives of government, science, culture, media and universities.