Enterprise integration is the software that carries each changed record between a company's applications, so that every application holds the same data. A mid-sized company runs a few hundred applications. They include the ERP, the CRM in which the sales team tracks customers and deals, the payroll system, the warehouse system and the bank's system. Each of them holds a piece of the same order or the same customer.
Imagine a cosmetics brand in Chandigarh that sells on its own website. A customer orders a face cream for ₹649. The website records the order. The CRM must add the customer. The ERP must record the sale and reduce the stock. The warehouse system must tell a packer to pack the cream. Nobody should have to type the same order four times.
The work comes in two layers.
The upper layer connects applications through their APIs. An API is a fixed format in which one program asks another program for data, or sends it an instruction. An integration platform as a service (iPaaS) lets a team draw each connection on a screen, for example: when an order arrives on the website, create a sales order in the ERP. The platform then runs the connection every time, and records whether it worked. The newest platforms let the team describe the connection in words, and an AI agent decides which systems to call. This is called agentic integration.
The lower layer is older, and it has not gone away. Many systems still exchange files instead of API calls. Managed file transfer (MFT) delivers a file securely and on time, such as the file of supplier payments that must reach the bank by midnight. Retail chains and logistics companies still send orders in fixed formats called electronic data interchange (EDI). And workload automation runs the overnight batch jobs, such as closing the day's books, in the right order.
The two layers match two ways of moving data, which the page on batch and stream processing explains. The API layer sends each change within seconds. The file layer sends many changes together, at fixed times.
Enterprise integration connects applications. Copying whole databases into a data warehouse for analysis is a related job, done with ETL and ELT tools. A company that wants AI agents to act in its systems also gives them access through the integration platform.