What is software integration?

Every company pays a copy-paste tax and almost none of them measure it. Someone reads an order in one screen and types it into another, exports a spreadsheet on Monday morning, reconciles two lists that should have agreed automatically, and answers a customer with information that was accurate yesterday. Software integration is the removal of that tax: the applications talk directly, so the shop order creates the invoice, reserves the stock, generates the courier consignment and updates the customer record without a human intermediary. Technically it happens through published interfaces, event notifications, message queues or middleware that translates between systems, and the details rarely matter to the buyer. Three things do. Integration is usually cheaper than replacing perfectly good systems with one large suite that does everything moderately well. It has a maintenance cost, because both sides evolve and connections break when they do. And the quality of the result depends far more on agreeing whose data is authoritative for each field than on the code — the integrations that fail commercially are almost always the ones where two systems each believed they owned the customer record.