Accessible Rich Internet Applications (ARIA)

In a nutshell:

• describes semantics
• for markup
• that can't be otherwise inferred
• but is often implemented via scripting.

All via the role and other supporting attributes.

The role Attribute

Names an ARIA role associated with the element.

• An indicator of type,
• that typically represents semantics,
• associated with UI interaction.

Example: menu, tab, tabpanel, math, article, presentation ... (see role categorization for more)

Properties and States

Additional properties and states are:

• represented by attributes
• on the same element,
• that contain various values,
• and may refer to other elements.

<div class="dropdown">
  <button class="btn btn-default dropdown-toggle" type="button" id="dropdownMenu1" data-toggle="dropdown" aria-expanded="true">
    Dropdown
    <span class="caret"></span>
  </button>
  <ul class="dropdown-menu" role="menu" aria-labelledby="dropdownMenu1">
     ...