The understandable principle
This page is for everyone on a public website team. The third WCAG principle says that information and the operation of the interface must be understandable (https://www.w3.org/TR/WCAG22/). For public bodies it overlaps with plain language duties: people must understand what the government tells them and asks of them.
Contents
3.1 Readable
| Role | Does |
|---|---|
| Developers | <html lang> per siteaccess; lang on passages from another language |
| Editors | plain language: short sentences, common words, active voice, terms explained; abbreviations written out at first use |
| Administrators | one siteaccess and one translation per language (Content languages) |
Admin4 writes lang from the siteaccess locale. For plain language, the US federal guidance at
https://www.plainlanguage.gov/ is a free reference. See "Language of the page and its parts".
3.2 Predictable
| Role | Does |
|---|---|
| Designers | the same navigation in the same place on every page; the same function with the same name |
| Developers | no change of context on focus or on selection alone (a select that submits itself) |
| Editors | link to documents and new windows with a warning in the text |
Shared headers and footers keep navigation consistent (Shared header and footer).
3.3 Input assistance
| Role | Does |
|---|---|
| Developers | errors identified in text, linked from a summary that takes focus; suggestions for fixing; values kept |
| Designers | visible labels and instructions before fields |
| Editors | clear field descriptions in form classes; a confirmation page that says what happens next |
| Administrators | sign-in that works with password managers; consider what two-step sign-in asks of users (3.3.8) |
Admin4: error summary and field messages (AdminFormErrorsTest.php). See "Accessible forms".
Related pages
- Accessible forms
- Accessible content for editors
- Mapping WCAG 2.2 AA to Exponential
- Free documentation: this page is free to copy, translate and improve under the GNU FDL 1.3.
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