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HTML

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CSS

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CSS Base

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <h1>Help to remember jQuery selectors I regularly mixup</h1>

<p>In the following examples the .hightlight class is toggled for matching elements on click to show the selection.</p>

<p><a href="https://api.jquery.com/">jQuery Docs are here</a>.</p>

<dl>
  <dt>.find()</dt>
  <dd>
    <a href="#target" id="target-find">&lt;a&gt;I use jQuery’s .find() selector to find all &lt;i&gt; elements which are my descendants &mdash; 
      <i>&lt;i&gt;Like me!&lt;/i&gt;</i>&lt;/a&gt;</a>
  </dd>
</dl>

<dl>
  <dt>.next()</dt>
  <dd>
    <a href="#target" id="target-next">&lt;a&gt;I use jQuery’s .next() selector to find my immediately following sibling I am looking for, in this case I want to find my next  &lt;brother&gt;.&lt;/a&gt;</a>
    <div class="brother">&lt;brother&gt;I am a sibling of that &lt;a&gt; above me.&lt;/brother&gt;</div>
    <div class="brother">&lt;brother&gt;I am also a sibling of &lt;a&gt;, but alas I am not .next() to &lt;a&gt; and for this, I am sad.&lt;/brother&gt;</div>
  </dd>
</dl>

<dl>
  <dt>.siblings()</dt>
  <dd>
    <a href="#target" id="target-siblings">&lt;a&gt;I use jQuery’s .siblings() selector to find all of the type of siblings I am looking for, in this case I want to find my &lt;sisters&gt;.&lt;/a&gt;</a>
    <div class="brother">&lt;brother&gt;I am a sibling and brother of that &lt;a&gt; above me.&lt;/brother&gt;</div>
    <div class="sister">&lt;sister&gt;I am a sibling and sister of that &lt;a&gt; above me.&lt;/sister&gt;</div>
    <div class="sister">&lt;sister&gt;I am a sibling and sister of that &lt;a&gt; above me.&lt;/sister&gt;</div>
    <div class="brother">&lt;brother&gt;I am a sibling and brother of that &lt;a&gt; above me.&lt;/brother&gt;</div>
    <div class="sister">&lt;sister&gt;I am a sibling and sister of that &lt;a&gt; above me.&lt;/sister&gt;</div>
  </dd>
</dl>

<dl>
  <dt>.closest()</dt>
  <dd>
    <section>
      <div>&lt;section&gt;&lt;div&gt;
        <a href="#target" id="target-closest">&lt;a&gt;I use jQuery’s .closest() selector to find my closest ancestor that matches what I am looking for, in this case a &lt;section&gt; element.&lt;/a&gt;</a>&lt;/div&gt;&lt;/section&gt;</div>
    </section>
  </dd>
</dl>

<dl>
  <dt>.first()</dt>
  <dd>
    <a href="#target" id="target-first">&lt;a&gt;I use jQuery’s .first() selector to find the first element in a set I'm looking for, in this case I want to find the first &lt;li&gt; in my sibling &lt;ul&gt;.&lt;/a&gt;</a>
    <ul>
      <li>First</li>
      <li>Second</li>
      <li>Third</li>
    </ul>
  </dd>
</dl>
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CSS 

              
                body {
  padding: 1em;
}
dl {
  background: #ddd;
  padding: 1em;
}
.highlight {
  background: #ff00ff;
}
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JS 

              
                $("#target-find").click(function() {
  $(this).find("i").toggleClass("highlight");
});

$("#target-next").click(function() {
  $(this).next(".brother").toggleClass("highlight");
});

$("#target-siblings").click(function() {
  $(this).siblings(".sister").toggleClass("highlight");
});

$("#target-closest").click(function() {
  $(this).closest("section").toggleClass("highlight");
});

$("#target-first").click(function() {
  $("#target-first + ul li").first().toggleClass("highlight");
});
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999px

Console