A back office is a part of most corporations where tasks dedicated to running the company itself take place. The term comes from the building layout of early companies where the front office would contain the sales and other customer-facing staff and the back office would be those manufacturing or developing the products or involved in administration but without being seen by customers. Although the operations of a back office are usually not thought of, they are a major contributor to a business. Examples of back-office tasks include IT departments that keep the phones and computers running (operations architecture), accounting, and human resources. These tasks are often supported by back-office systems: secure e-commerce software that processes company information (e.g. a database). A back-office system will keep a record of the company�s sales and purchase transactions, and update the inventory as needed. Invoices, receipts, and reports can also be produced by the back-office system. In banking, the back office includes a heavyweight IT processing system that handle position keeping, clearance, and settlement. In investment firms, the back office includes the administrative functions that support the trading of securities, including recordkeeping, trade confirmation, trade settlement, and regulatory compliance. If used in sales, the back office would include functions that fulfill customers� orders and would usually include the duties involved in customer-support call centers.