INDUSTRIES are classified into four categories:Public Sector Industries-These industries are owned and managed by government agencies.Example - Chittaranjan Locomotive Works, The Integral Coach Factory, Perambur, Iron and Steel Plants at Bhilai and Durgapur.Private Sector Industries -These industries are owned and managed by individuals or groups of people.Example- Tata Iron and company, Reliance Industries, Aditya Birla Group of Industries, Reliance Jio.Joint Sector Industries-These industries are owned and managed jointly by private firms and government agencies.Example - Oil India Limited, Gujarat AlkaliesCooperative Sector Industries- These industries are owned and managed by a gaggle of individuals who form their own cooperative society.They're generally producers of the staple.Example - Dairy cooperatives, Handloom industry.Kochi Refinery may be a PETROLEUM refinery within the city of Kochi in Kerala, India.It's the most important public-sector refinery in India with a production capacity of 31.54 million tonnes per annum.CHENNAI Petroleum Corporation Limited (CPCL) Chennai Petroleum Corporation Limited, formerly referred to as Madras Refineries Limited (MRL), was formed in 1965 as a venture between the GOVT of India (GOI), AMOCO, and therefore the National Iranian company (NIOC).Gujarat State Fertilizer Company was incorporated in 1962 and its plants went into the assembly of fertilizers in 1967.Reliance Jio Infocomm Limited, doing business as Jio, is an Indian TELECOMMUNICATIONS company and a subsidiary of Jio Platforms, headquartered in Mumbai, Maharashtra, India.It operates a national LTE network with coverage across all 22 telecom circles.