1) Depreciation is the systematic allocation of the cost of a fixed asset over its useful life to match the cost with the economic benefits generated by the asset.
2) Without depreciation accounting, the entire cost of a fixed asset would be recognized in the year of purchase, providing a misleading view of an entity's profitability.
3) The straight-line method is the simplest way to calculate depreciation by subtracting salvage value from original cost and dividing by estimated useful life in years.