The dictionary meaning of the term "audit" is check, review, inspection, etc. There are various types of audits prescribed under different laws like company law requiring a company audit, cost accounting law requiring a cost audit, etc. The Income-tax Law requires the taxpayer to get the audit of the accounts of his business/profession from the viewpoint of Income-tax Law.
Section 44AB gives the provisions relating to the class of taxpayers who are required to get their accounts audited from a chartered accountant. The audit under section 44AB aims to ascertain the compliance of various provisions of the Income-tax Law and the fulfilment of other requirements of the Income-tax Law. The audit conducted by the chartered accountant of the accounts of the taxpayer in pursuance of the requirement of section 44AB is called tax audit.
The chartered accountant conducting the tax audit is required to give his findings, observation, etc., in the form of an audit report. The report of tax audit is to be given by the chartered accountant in Form Nos. 3CA/3CB and 3CD.