Glossary · Accessibility term
Normative
Normative means required for conformance. The main content of WCAG is normative, and the parts anything ever gets tested against are the success criteria and the five conformance requirements alongside them. The four principles and thirteen guidelines above them set the objectives, and the guidelines are not testable at all, so nothing is ever measured against one. The line also runs inside the standard rather than only around it. Introductory material, appendices, sections marked non-normative, diagrams, examples and notes are all informative, so a note sitting under a success criterion tells you how to read the rule rather than adding to it. Techniques and Understanding pages sit outside WCAG altogether, and they are informative too.
In practice
When someone tells you a technique is required, check which document it came from. If it is a technique, an Understanding page or an example, it is advice. The success criterion is the rule.
Check where the sentence sits, too, because the boundary runs through the standard as well as around it. A success criterion is binding and the notes underneath it are not, so a note is W3C telling you how it reads the rule rather than adding to it. W3C goes further on its own techniques and cautions against requiring them, on the grounds that the only thing anyone should require is meeting the success criteria.
This is not a licence to ignore the techniques. They are the accumulated answer to how people actually pass, and departing from them means you own the argument for why your way works.
Why it matters
Audits go wrong in both directions here. A reviewer who insists on one technique is enforcing something that was never binding, and a team that hears informative and stops reading tends to fail the criterion those techniques were written to document. The word is also relative to a document rather than a property of a sentence, and other W3C accessibility specifications draw the line elsewhere, so a habit carried across from one of them will get WCAG wrong.
What is binding
1.1.1 says non-text content has a text alternative serving the equivalent purpose. That is normative. H37, which says to use the alt attribute on img elements, is one sufficient technique and is informative. An SVG carrying an accessible name that does the same job the picture does passes 1.1.1 without going near H37, because not implementing a sufficient technique is not the same as failing the rule it was written for. Note what still has to be true. A name that says nothing useful is not a text alternative just because the tree has something in it.
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Related terms
Knowing the word is the easy part.
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