According to Marketing Management by Keller and Kotler (15th edition),
- Industry. A group of firms that offer a product or class of products that are close substitutes for one another.
According to the Strategic Management by Parnell (4th edition),
- Industry. A group of competitors that produces similar products or services.
- Main wikipage: Economy segment
|Primary||Raw materials||Agriculture, mining|
|Secondary||Manufacturing||Food, clothing, wood, printing, petroleum, chemical, metal, transport, machinery|
|Infrastructure||Construction, energy supply, water supply, waste disposal|
|Quaternary||Digital||Telecommunication, multimedia, information technology, digital publishing, broadcasting, Internet service, web search, data processing|
- Main wikipage: Industrial classification