What language is primarily used in BPEL processes?

BPEL, which stands for Business Process Execution Language, is a language specifically designed for defining business processes based on web services. The primary format used in BPEL processes is XML (eXtensible Markup Language). This is because XML provides a flexible and standardized way to structure data and communicate between different systems, which is essential for web services orchestration.

BPEL processes utilize XML to define the various activities, sequences, and management of execution flow, allowing them to interact with different web services. By being grounded in XML, BPEL can seamlessly integrate with other technologies and standards that also leverage XML, such as SOAP (Simple Object Access Protocol) and WSDL (Web Services Description Language).

The other options, while relevant in different contexts, do not serve as the primary language for BPEL processes. Java is a programming language that can be used to implement business logic but is not the basis of BPEL. WSDL is indeed used to describe web services but is not the language in which business processes are executed. HTML is used for web page structure and is not applicable to BPEL processes at all.