Bookkeeping is the recording of financial transactions, and is part of the process of accounting in business and other organizations. It involves preparing source documents for all transactions, operations, and other events of a business. Transactions include purchases, sales, receipts and payments by an individual person or an organization/corporation. There are several standard methods of bookkeeping, including the single-entry and double-entry bookkeeping systems. While these may be viewed as "real" bookkeeping, any process for recording financial transactions is a bookkeeping process.

The person in an organisation who is employed to perform bookkeeping functions is usually called the bookkeeper (or book-keeper). They usually write the daybooks (which contain records of sales, purchases, receipts, and payments), and document each financial transaction, whether cash or credit, into the correct daybook—that is, petty cash book, suppliers ledger, customer ledger, etc.—and the general ledger. Thereafter, an accountant can create financial reports from the information recorded by the bookkeeper. The bookkeeper brings the books to the trial balance stage, from which an accountant may prepare financial reports for the organisation, such as the income statement and balance sheet.