Muhammad Aamir's presentation defines the accrual concept as recording business transactions when they occur rather than when related payments are received or made. This accrual basis of accounting provides more useful financial information. Examples given include an airline not recording ticket sales as revenue until flights occur, and an accounting firm expensing a portion of prepaid rent each quarter based on time elapsed. The accrual concept signifies recording expenses when services are used and bills received, rather than when payment is made. It allows businesses to better understand actual expenses and income over time and calculate net profit accordingly.