Accountancy (British English) or accounting (American English) is the measurement, disclosure or provision of assurance about information that helps managers and other decision makers make resource allocation decisions. Financial accounting is one branch of accounting and historically has involved processes by which financial information about a business is recorded, classified, summarized, interpreted, and communicated. Auditing, a related but separate discipline, is the process whereby an independent auditor examines an organization's financial statements in order to express an opinion (with reasonable but not absolute assurance) as to the fairness and adherence to generally accepted accounting principles, in all material respects.
Practitioners of accountancy are known as accountants. Officially licensed accountants are recognized by titles such as Chartered Accountant (UK) or Certified Public Accountant (US).
Accountancy attempts to create accurate financial reports that are useful to managers, regulators, and other stakeholders such as shareholders, creditors, or owners. The day-to-day record-keeping involved in this process is known as book-keeping.
At the heart of modern financial accounting is the double-entry book-keeping system. This system involves making at least two entries for every transaction: a debit in one account, and a corresponding credit in another account. The sum of all debits should always equal the sum of all credits. This provides an easy way to check for errors. This system was first used in medieval Europe, although some believe that the system dates back to Ancient Greece.
According to critics of standard accounting practices, it has changed little since. Accounting reform measures of some kind have been taken in each generation to attempt to keep book-keeping relevant to capital assets or production capacity. However, these have not changed the basic principles, which are supposed to be independent of economics as such.