The main difference comes from the original rules and regulations which were published by both accounting bodies and their managements. You need to understand that both are accounting bodies and their rules are well written. To know the clear difference between IFRS and IAS you need to read their rules and regulations first to understand the overall difference between both accounting systems. First you need to understand that IAS as their rules and regulations were published through 1973 and 2001 but the IFRS were published by the International Accounting Standards Board (IASB).
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You also need to understand that IAS and its standards which basically stand for International Accounting Standards while the IFRS submits the International Financial Reporting Standards which has different rules and regulations. You also need to understand that IAS standards were published through 1973 to 2001 while the IFRS standards are still coming. You need to look regarding all the different aspects of the system and then make out a decision that either these systems are the same or not.
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