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  <title>async vs defer Example</title>
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  <h1>async vs defer</h1>
  <table>
    <tr><th>Attribute</th><th>Download</th><th>Execute</th></tr>
    <tr><td><code>async</code></td><td>Parallel</td><td>As soon as ready (order not guaranteed)</td></tr>
    <tr><td><code>defer</code></td><td>Parallel</td><td>After HTML is parsed (order preserved)</td></tr>
    <tr><td>(none)</td><td>Blocks parsing</td><td>Immediately when encountered</td></tr>
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  <p class=hint>Use <code>async</code> for independent scripts like analytics. Use <code>defer</code> when scripts depend on DOM or each other.</p>
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HTML async Attribute — async vs defer