A state-owned enterprise in India is called a public sector undertaking or a public sector enterprise. Those companies are owned by the union government of India or one of the many state or territorial governments or both. A career with PSU requires , a strong and in-depth technical knowledge and understanding of core engineering principals. Gate is one such exam, where ones technical and general aptitude is tested. Today more than 15000 chemical engineering students are writing Gate exam for aspiring jobs in top PSUs. The regular PSUs recruiting chemical engineers through gate are:
ONGC, IOCL, GAIL, NPCIL, EIL.
The central government organizations BARC and DRDO also recruit through Gate regularly. Some PSUs like RCFL, BHEL, NFL etc recruit occasionally through Gate exam and through their respective online papers.

GATE exam is conducted for Master of Engineering (ME), Masters in Technology (MTech) and direct PhD admissions to Indian Institutes of Technology (IITs), National Institutes of Technology (NITs), Indian Institutes of Information Technology (IIITs) and other institutes/universities across India. Some people aspire for higher studies so Gate exam is perfect exam to prepare to aspire higher studies in IISC/IITs/NITs.