The International Digital Publishing Forum (IDPF) was a trade and standards association for the digital publishing industry, set up to establish a standard for electronic book publishing.
Starting from the Open eBook (OEB) Publication Structure (1999), created loosely around HTML, it then defined the OPS (Open Publication Structure), the OPF (Open Packaging Format) and the OCF (Open Container Format).
While the basic standards are established (pages, hyperlinks, definition of table of contents, authors, etc.
Standards for ecommerce (including digital rights management) are tied to the way the ebook is sold or delivered and are therefore controlled by vendors.
On January 30, 2017, IDPF was combined with and absorbed into the World Wide Web Consortium.