The double entry system was first evolved by Luca Pacioli, who was a Fransiscan Monk of Italy. With the passage of time, the system has gone through lot of development stages. It is the only method fulfilling all the objectives of systematic accounting. It recognizes the two fold aspect of every business transaction.
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Double entry system is the system under which each transaction is regarded to have two fold aspect and both the aspects are recorded to obtain complete record of dealings. Double entry system of book keeping adheres to the rule, that for each transaction the debit amount must equal the credit amount. That is why this system is called double entry.