In mercantile system, expenses are considered as expenses during the period to which they pertain. Similarly, incomes are considered to be incomes during the period to which they pertain. This system of accounting is considered to be more ideal. On the hand, in cash system, expenses are considered to be expenses only when they are paid for and the incomes are considered to be income when they are actually received. This system of accounting is mainly used by the organizations established not for earning the profits.