Add note about "input" not just meaning HTML input elements

Author: patrickhlauke

understanding/21/identify-input-purpose.html

@@ -29,6 +29,7 @@ <h2>Intent of this Success Criterion</h2>
   <p>In addition to repurposing this taxonomy, when the autocomplete attribute technique is used to meet this Success Criterion, browsers and other user-agents can suggest and 'autofill' the right content by autocompleting these fields based on past user input stored in the browser. By defining more granular definitions of common input purposes, for example “Birthday” (<code>autocomplete="bday"</code>), browsers can store personalized values for each of these fields (the user's birthday date). The user is relieved of having to type the information and can instead confirm or, if needed, change the value of the field, a significant benefit for users with memory issues, dyslexia, and other disabilities. Because the <code>autocomplete</code> values are independent of language, users that may not be familiar with the text used to visually identify user input fields (the label) can still have that purpose consistently identified to them due to the fixed taxonomy of terms.</p>
   <p>If an input field accepts two different types of input purpose (as in combined user name/user email fields) and the technology used does not allow multiple purpose values to be defined, it is valid to provide either one or the other value or leave out the designation of input purpose altogether.</p>
   <p>When the user agent and assistive technology support for other metadata formats matures, metadata schemes like the <a href="https://www.w3.org/TR/adapt-symbols/">WAI-Adapt: Symbols Module</a> may be used in addition or instead of the HTML autocomplete attribute to identify the purpose of input fields. They can also support automated adaptations that identify and match author-provided input labels to defined vocabularies or symbols that are used instead for labelling inputs.</p>
+  <p class="note">The term <q>input</q> is used here as a generic way to refer to form controls that accept user input. For instance, in HTML, it is not limited to the <code>&lt;input&gt;</code> element, but also covers other controls such as <code>&lt;select&gt;</code>.</p>
 </section>
 
 <section id="benefits">