Question

how to write preface on the topic Industry​

Answer 1

Industries are part of the secondary activity. Secondary activities or manufacturing converts raw material into products of more value to people. Industry refers to economic activities concerned with the production of goods, extraction of services and provision or services. Hence we can say that Industries are concerned with:

Production of good (steel energy)
Extraction of minerals (coal mining)
Provision for services (tourism)
There are also Emerging Industries: ‘Sunrise Industries’
Classification of Industries

1. Raw material

Agro-based industries: These industries use plants and animal-based products as their raw materials. Examples, food processing, vegetable oil, cotton textile, dairy products, and leather industries.
Mineral based industries: Mineral-based industries are based on mining and use ‘mineral ore‘ as raw material. These industries also provide to other industries. They are used for heavy machinery and building materials.
Marine-based industries: Marine-based industries use raw materials from sea or ocean. Examples, fish oil.
Forest-based industries: These industries use raw materials from the forest like wood. The industries connected with forest are paper, pharmaceutical, and furniture.
2. Size

Size of industries are measured by how much money is invested, employee count and goods produced.

Small-scale industries: Small-scale industries have less capital and technology invested in them. There is often manual labour noticed here. Example, Basket weaving, pottery, and handicrafts.
Large-scale industries: Largescale industries are the exact opposite of small-scale industries. Here the capital invested is large and advanced technology is in use here. Example, Automobiles and Heavy Machinery.
3. Ownership

Private sector: Private industries are businesses that are owned and operated by an individual or group of individuals.
Public sector: Public industries are owned and managed by the government. Example, Hindustan Aeronautics Limited (HAL)
Joint sector industries: These industries are jointly operated by the state and individuals. Example, Maruti Udyog.
Cooperative sector industries: Cooperative industries are operated by the suppliers, producers or workers of raw material. Example, Amul India.