Double-entry bookkeeping, also known as double-entry accounting, is a method of bookkeeping in which every financial transaction is recorded with equal and opposite entries - thus "balancing the books
Della mercatura e del mercante perfetto by Benedetto Cotrugli, cover of 1602 edition; originally written in 1458
Portrait of the Italian Luca Pacioli, painted by Jacopo de' Barbari, 1495, (Museo di Capodimonte). Pacioli is regarded as the Father of Accounting.