Heavy industry, group of companies, or productive organizations that produce or supply goods, services, or sources of income. In economics, industries are generally classified into primary, secondary, tertiary, and quaternary; Secondary industries are further classified as heavy and light.

Primary industry

This sector of a nation's economy includes agriculture, forestry, fishing, mining, quarrying, and mineral extraction. It can be divided into two categories: genetic industry, including the production of raw materials that can be increased through human intervention in the production process; and extractive industry, including the production of exhaustible raw materials that cannot be increased by cultivation.

Genetic industries include agriculture, forestry, and livestock, and fishing, all of which are subject to the scientific and technological improvement of renewable resources. Extractive industries include mineral extraction, stone mining, and mineral fuel extraction.

The primary industry tends to dominate the economies of underdeveloped and developing nations, but as secondary and tertiary industries develop, their share in economic output tends to decline.

Secondary industry

This sector, also called the manufacturing industry, takes the raw materials supplied by primary industries and processes them into consumer goods, or also processes goods that other secondary industries have transformed into products, or builds capital goods used to make consumer goods and I do not consume. The secondary industry also includes energy-producing industries (e.g. hydroelectric industries) as well as the construction industry.

Secondary industry can be divided into the heavy or large-scale industry and light or small-scale industry. The large-scale industry generally requires a large capital investment in plant and machinery, serves a large and diverse market that includes other manufacturing industries, has a complex industrial organization, and often a skilled and specialized workforce, and generates a large volume of production. Examples would include petroleum refining, iron, and steel manufacturing (see metallurgy), motor vehicle and heavy machinery manufacturing, cement production, non-ferrous metal refining, meat packaging, and power generation. hydroelectric.

Light or small-scale, the industry can be characterized by non-durability of manufactured products and less capital investment in plant and equipment, and can involve non-standard products, such as custom or craftwork. The workforce may be low-skilled, as in textile work and garment making, food processing, and plastics manufacturing, highly-skilled, as in electronic and computer equipment manufacturing, precision instruments, gemstone cutting, and crafts.

Tertiary industry

This broad sector also called the service industry includes industries that, although they do not produce tangible goods, provide intangible services or profits or generate wealth. This sector generally includes both private and government companies.

Industries in this sector include, but are not limited to, banking, finance, insurance, investment, and real estate services; wholesale, retail and resale trade; transport; professional, consulting, legal and personal services; tourism, hotels, restaurants, and entertainment; repair and maintenance services; and health, social welfare, administrative, police, security and defense services.

Quaternary industry

An extension of the tertiary industry that is often recognized as its sector, the quaternary industry, deals with information-based or knowledge-oriented products and services. Like the tertiary sector, it comprises a combination of private and government initiatives. Industries and activities in this sector include information systems and information technology (IT); research and development, including technological development and scientific research; financial and strategic analysis and consulting; media and communications technologies and services; and education, including teaching and educational technologies and services.