Secondary sector of the economy

In macroeconomics, the secondary sector of the economy is an economic sector in the three-sector theory which describes the role of manufacturing. It encompasses the industries which produce a finished, usable product or are involved in construction.

This sector generally takes the output of the primary sector (i.e. raw materials) and creates finished goods suitable for use by other businesses, for export, or for sale to domestic consumers (via distribution through the tertiary sector). Many of these industries consume large quantities of energy and require factories and machinery; they are often classified as light or heavy based on such quantities. They also produce waste materials and waste heat that may cause environmental problems or cause pollution (see negative externalities). Examples include textile production, car manufacturing, and handicraft.[1]

Manufacturing is an important activity in promoting economic growth loand development. Nations that export manufactured products tend to generate higher marginal GDP growth which supports higher incomes and marginal tax revenue needed to fund quality-of-life initiatives such as health care and infrastructure in the economy. The field is an important source for engineering job opportunities. Among developed countries, it is an important source of well-paying jobs for the middle class to facilitate greater social mobility for successive generations on the economy. Currently, an estimated 20% of the labor force in the United States is involved in the secondary industry.[2]

The secondary sector depends on the primary sector for the raw materials necessary for production. Countries that rely on agriculture and other raw materials i.e. (primary sector), grow slowly and remain under-developed or developing economies. The value addition after the processing of goods creates for higher profitability, which accounts for the growth of developed economies.

20 largest Countries by Industrial Output (in PPP terms) according to the IMF and CIA World Factbook, at peak level as of 2020

Economy	Countries by Industrial Output (in PPP terms) at peak level as of 2020 (billions in USD)
(01)  China	11,261
(—)  European Union	5,729
(02)  United States	4,093
(03)  India	2,604
(04)  Japan	1,719
(05)  Indonesia	1,549
(06)  Russia	1,422
(07)  Germany	1,364
(08)  South Korea	912
(09)  Saudi Arabia	840
(10)  Mexico	835
(11)  Turkey	763
(12)  Brazil	720
(13)  United Kingdom	639
(14)  France	597
(15)  Italy	587
(16)  Iran	578
(17)  Canada	537
(18)  Poland	517
(19)  Thailand	499
(20)  Egypt	490
The twenty largest countries by industrial output (in PPP terms) at peak level as of 2020, according to the IMF and CIA World Factbook.