Depreciation is a mandatory expense that must be recorded regardless of whether the business makes a profit or incurs a loss. As a charge against profit, it is deducted in the Profit and Loss account to determine the net operating result, ensuring that the cost of using long-term assets is matched against the revenue they help generate.

When using the provision for depreciation method, the asset account is maintained at its original cost price. The accumulated depreciation is recorded in a separate contra-asset account, allowing the historical cost to remain visible on the balance sheet.

The inventory system of depreciation, sometimes called the revaluation or appraisal method, involves assessing the value of an asset at the beginning and end of an accounting period. The difference between these two values represents the depreciation charge for that period, reflecting the actual decline in the asset's market value.

In accounting practice, the term 'Provision for Depreciation' is frequently used to represent the accumulated depreciation account. This account tracks the total amount of depreciation expense allocated to a fixed asset since its acquisition, effectively reducing the asset's book value on the balance sheet over its useful life.

Depreciation is the accounting process of allocating the cost of a tangible asset over its useful life. It reflects the consumption of the asset's economic benefits. By spreading the cost, businesses match expenses to the revenue generated by the asset, ensuring accurate financial reporting. It is not merely a measure of physical wear or market value fluctuations, but a systematic cost allocation method.

Gross investment represents the total expenditure on new capital goods. Net investment is the actual addition to the capital stock after accounting for the wear and tear of existing assets. Therefore, the difference between gross investment and net investment is the depreciation, which represents the consumption of fixed capital during the period.

Depletion is the systematic allocation of the cost of natural resources over their estimated period of extraction. These are referred to as wasting assets, such as oil wells, mines, or timberlands, which physically diminish as they are consumed.

Obsolescence refers to the loss of value of an asset caused by technological changes, new inventions, or shifts in market demand, rather than physical wear and tear. It is a primary factor in determining the useful life of an asset for depreciation purposes, as the asset may still be physically functional but economically inefficient.

Historical cost is a factual, verifiable figure representing the actual price paid to acquire an asset, making it the only non-estimated component in depreciation calculations. Conversely, useful life, residual value, and salvage value are all estimates based on management's judgment regarding how long an asset will be productive and what its value will be at the end of that period. These estimates are subject to periodic review and adjustment as circumstances change.

Land is considered a non-depreciable asset because it has an unlimited useful life and does not wear out, become obsolete, or get consumed through use. Unlike buildings or machinery, which lose value over time due to physical deterioration or technological obsolescence, land typically retains or increases its value.