A Public Sector Undertaking (PSU) is a government-owned corporation or company that operates in various sectors of the economy. These entities are established to provide essential services, promote economic development, and generate employment. PSUs are funded and managed by the government, ensuring that profits are reinvested for public welfare rather than distributed to private shareholders. In many countries, including India, PSUs play a crucial role in sectors like energy, transportation, and telecommunications. They help maintain strategic control over key resources and services, contributing to national interests and social objectives. Examples of PSUs include Indian Oil Corporation and Bharat Heavy Electricals Limited.