Depreciation methods are accounting techniques used to allocate the cost of a tangible asset over its useful life. Common methods include straight-line depreciation, where the asset's cost is evenly spread over its lifespan, and declining balance depreciation, which allows for larger deductions in the earlier years. These methods help businesses accurately reflect the value of their assets on financial statements. By using depreciation, companies can match the cost of an asset with the revenue it generates, providing a clearer picture of profitability and financial health over time.