WebM
multimedia container format with VP8 or VP9 video and Vorbis or Opus audio
WebM is an audiovisual media file format. It is primarily intended to offer a royalty-free alternative to use in HTML video and HTML audio elements. It has a sister project for images: WebP. The development of the format is sponsored by Google, and the corresponding software is distributed under a BSD license. WebM was a collaborative effort first released in 2010.
The WebM container is based on a profile of Matroska. WebM initially supported VP8 video and Vorbis audio streams. In 2013, it was updated to accommodate VP9 video and Opus audio. It also supports the AV1 codec.
Vendor support
Software
Native WebM support by Mozilla Firefox, Opera, and Google Chrome was announced at the 2010 Google I/O conference. Internet Explorer 9 requires third-party WebM software.
This brief starts where responsible research should: with the source description of “WebM” as multimedia container format with VP8 or VP9 video and Vorbis or Opus audio. Everything that follows is an evidence route, not borrowed authority.
Why this record matters
The subject matters to the general reference register because the source frames it as multimedia container format with VP8 or VP9 video and Vorbis or Opus audio. Its deeper value depends on whether names, dates, institutions and citations support that framing.
Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Sep 22, 2026. The linked authority identifier is Q309440. 1 of 2 selected statements include explicit references; 1 carry qualifiers and 0 use preferred rank. The first chronological checks are 2010 and 2013.
Overview language is designed for orientation and should not be treated as a substitute for the evidence cited beneath it. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Use the entry as an orientation point, then follow its citations and revision history. Names, dates and institutional relationships should be checked against the original record.
- Subject orientation
- Search vocabulary
- Locating named sources
The closest primary source, responsible institution and strongest cited specialist reference.
Three-step research path
- Establish the record: confirm the title “WebM”, its source revision and the description used here.
- Expand the search: follow WebM primary sources, WebM archive and WebM research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “WebM”?
- What terminology or title could unlock a more precise catalogue search?
- Which cited source is closest to the event, object or claim?
Search terms from this dossier
This entry incorporates text from “WebM” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.