IDoc (Intermediate Document) is a standard data structure used in SAP systems for exchanging information between different SAP applications or external systems. It serves as a format for electronic data interchange (EDI), enabling seamless communication of business transactions such as orders, invoices, and delivery notifications. IDocs are structured into segments and fields, allowing for flexible data representation. They can be triggered by events within the SAP system or sent manually, facilitating both inbound and outbound data processing. This makes IDocs a crucial component for integrating various business processes in SAP environments.