Accounting principles are the basic rules and guidelines followed while recording financial transactions in the books of accounts. These principles help maintain accuracy, consistency, and transparency in financial statements. Depreciation refers to the decrease in the value of a fixed asset over time due to usage, wear and tear, or obsolescence. It is treated as an expense and recorded in the Profit and Loss Account. Common methods of depreciation include the Straight Line Method (SLM) and Written Down Value Method (WDV). Journal entries are used to record financial transactions in the accounting books based on the golden rules of accounting. For example, when salary is paid, the entry is: Salary A/c Dr To Cash/Bank A/c These entries help maintain proper accounting records and assist in preparing financial statements.