Hello sai,

As per your Query this is the difference between government company and public sector undertakings,

A government company is a company which can be runs under the state government or central government

A Public sector undertakings(PSU) is a state owned enterprise  in India is called a public sector undertaking or a public sector enterprise. Those companies that are owned by the union government of India or one of the many state or territorial governments or both. The company stock needs to be majority-owned by the government to be a PSU.

Hope You Understand.................................

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