Articles 148 to 151: how the Comptroller and Auditor General of India is created and protected
Background
The office of the Comptroller and Auditor General of India is created by Article 148 of the Constitution, as the institution sets out on its own website. The Comptroller and Auditor General is appointed by the President by warrant under his hand and seal, and can be removed from office only in the same manner and on the same grounds as a Judge of the Supreme Court. Before entering office he makes an oath or affirmation before the President, or before some person appointed in that behalf by the President, in the form set out in the Third Schedule. He is not eligible for any further office under the Government of India or under the Government of any State after he has ceased to hold office. The administrative expenses of his office, including all salaries, allowances and pensions payable to or in respect of persons serving in that office, are charged upon the Consolidated Fund of India. Article 149 lays down his duties and powers, Article 150 the form of accounts of the Union and of the States, and Article 151 the audit reports.
In plain words
CAG Comptroller and Auditor General of India — The constitutional auditor of the Union and the States, whose office Article 148 creates.