Entities, Structured Data, and HTML5 Browser APIs

This chapter collects several important HTML5 extras that improve content clarity, discoverability, and browser-powered features.

HTML Entities

Entities let you display reserved or special characters safely.

Examples:

< for <
> for >
& for &
" for "
© for ©

Example:

<p>Use &lt;section&gt; for grouped content.</p>

Structured Data

Structured data helps machines understand what your content represents.

Microdata Attributes

itemscope
itemtype
itemprop
itemid
itemref

Example:

<article itemscope itemtype="https://schema.org/Article">
    <h1 itemprop="headline">Learning HTML5</h1>
    <p itemprop="author">Sam Lee</p>
</article>

HTML5 Browser APIs Often Used with HTML

Local Storage

Purpose:

saves simple key-value data in the browser

Geolocation

Purpose:

can request the user's location with permission

Drag and Drop

Purpose:

supports dragging interface items between targets

History API

Purpose:

lets apps update browser history during navigation

These APIs are mostly controlled with JavaScript, but HTML often provides the elements and attributes they connect to.