A tax audit under section 44AB of the Income-tax Act tests whether the books support the return and whether the particulars required in Form 3CD have been correctly stated. Turnover, presumptive-tax thresholds, and the nature of the business decide when the audit is compulsory.
Work includes reconciling the financial statements with the tax computation, reviewing allowances and disallowances, checking TDS and reporting clauses, and filing the audit report within the statutory due date. Early scoping reduces last-minute adjustments that otherwise delay the ITR.