BPEL is a convergence of language features from IBM’s Web Service Flow Language (WSFL) that uses a directed graph approach and Microsoft’s XLANG, which is the orchestration language, used in BizTalk server and has a block-structured approach. Both WSFL and XLANG are now superseded by the BPEL specification.

BPEL 1.0 was jointly developed by IBM, BEA, SAP, Siebel, and Microsoft in August 2002. In April 2003, BPEL 1.1 was submitted to OASIS to obtain even broader industry acceptance and open standardization.

BPEL is a Markup language for composing a set of discrete services into an end-to-end process flow