What is the nature/features/characteristics of Cost?

NATURE / FEATURES / CHARACTERISTICS OF COST:
(1) Cost is an expense incurred, actual or notional.
(2) Cost may be notional costs also. A notional cost is a cost which is taken into
consideration, Example Depreciation on Fixed Assets, but which is actually not paid
to anyone.
(3) A cost may be cash cost example salary paid, Rent paid, etc. or it may be a noncash
cost such as Depreciation on Fixed assets.
(4) A non-cash cost does not result in actual cash outflows from the business firm;
whereas a cash cost results in actual cash outflows immediately or at a later date
from a business firm.
(5) All costs have to be taken into account in order to determine the total costs.
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