# Attribute “xmlns:rdf” not allowed here. > Canonical HTML version: https://rocketvalidator.com/html-validation/attribute-xmlns-rdf-not-allowed-here > Attribution: Rocket Validator (https://rocketvalidator.com) > License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) The `xmlns:rdf` attribute declares the RDF namespace that SVG editors use for the metadata block in a drawing, and HTML doesn't allow prefixed namespace declarations on `` or any other element. Inkscape SVG files, such as those saved by Inkscape 0.92, declare `xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"` on the root `` element, next to `xmlns:dc` and `xmlns:cc`. RDF (Resource Description Framework) is the W3C model for describing things as statements, and the `rdf:` namespace holds its core terms. Inkscape uses them to build the `` block. `` wraps the description, `rdf:about=""` says it is about this file, and `rdf:resource` gives a property a URI as its value, such as the Dublin Core type `StillImage`. The title and format are Dublin Core (`dc:`) terms, and the license is a Creative Commons (`cc:`) one. In a standalone `.svg` file, which is XML, all of this is valid. Inline the file in an HTML page and the block stops being RDF. The HTML parser doesn't process namespace declarations, so `xmlns:rdf` is a plain attribute with a colon in its name, and the validator reports it on ``, on `` and on any other element. The elements lose their namespace too. `` becomes an SVG element named `rdf:rdf`, which the validator reports as a completely-unknown element, along with every element nested in it. Delete `xmlns:rdf` together with the `` block. Removing only the declaration leaves all those unknown-element errors in place. Nothing in the block is drawn, so the image doesn't change. The same export usually declares `xmlns:dc`, `xmlns:cc`, `xmlns:sodipodi` and `xmlns:inkscape` too. Each gets its own message, and they all go in the same cleanup. If the page needs machine-readable facts about the image, such as who made it or what license it has, describe it in JSON-LD instead. A `