Presumptive taxation under section 44AE exempts taxpayers from maintaining books of account under section 44AA when income is declared as prescribed. A taxpayer who elects the presumptive taxation scheme under section 44AE and declares income as prescribed (per-vehicle monthly rates or actual receipts where applicable) is not required to maintain books of account under Section 44AA in respect of the business covered by that presumptive scheme; other activities remain subject to normal book-keeping obligations.