Comptroller and Auditor General of India is a constitutional body under Article 148 of the Constitution and is a supreme audit institution in the country meant to audit the central and state accounts. The Audit Reports on the accounts of the Union Government are prepared in several volumes, which are grouped on the basis of their subjects: Civil, Defence, Railways, Revenue Receipts and Commercial. The Reports contain major audit findings on the Ministries and offices under their control, including Autonomous Bodies and Public Sector Undertakings. Audit is categorized in three broad categories i.e. Financial, Compliance and Performance audits; The primary purpose of the Financial audit is to verify whether the financial statements (accounts of the Government) are properly prepared, complete in all respects and are presented with adequate disclosures. The Compliance audit examines the transactions relating to expenditure, receipts, assets and liabilities of the Government to ascertain whether the provisions of the Constitution, the applicable laws, rules, regulations and various orders and instructions issued by the competent authority are being complied with. The Performance audit is an independent assessment of the extent to which any organisation, programme or scheme operates economically, efficiently and effectively .
Audit Reports (Revenue) details about the taxes, revenue, duties and receipts. Many a times mining receipts is carried in this report providing details about the revenue streams in mining sector and any discrepancy or practice observed by the auditor.