title: How topSearch gets loaded in page.xml?
body: <p>I'm a newbie with Magento CE and I'm trying to learn to design a new theme. I've started studying the default desing package. There is one thing I cannot understand:</p>
  
  <p>This is the header section in page.xml:</p>
  
  <pre><code>&lt;block type="page/html_header" name="header" as="header"&gt;
                  &lt;block type="page/template_links" name="top.links" as="topLinks"/&gt;
                  &lt;block type="page/switch" name="store_language" as="store_language" template="page/switch/languages.phtml"/&gt;
                  &lt;block type="core/text_list" name="top.menu" as="topMenu" translate="label"&gt;
                      &lt;label&gt;Navigation Bar&lt;/label&gt;
                      &lt;block type="page/html_topmenu" name="catalog.topnav" template="page/html/topmenu.phtml"/&gt;
                  &lt;/block&gt;
                  &lt;block type="page/html_wrapper" name="top.container" as="topContainer" translate="label"&gt;
                      &lt;label&gt;Page Header&lt;/label&gt;
                      &lt;action method="setElementClass"&gt;&lt;value&gt;top-container&lt;/value&gt;&lt;/action&gt;
                  &lt;/block&gt;
              &lt;/block&gt;
  </code></pre>
  
  <p>And this is header.phtml:</p>
  
  <pre><code>&lt;div class="header-container"&gt;
      &lt;div class="header"&gt;
          &lt;?php if ($this-&gt;getIsHomePage()):?&gt;
          &lt;h1 class="logo"&gt;&lt;strong&gt;&lt;?php echo $this-&gt;getLogoAlt() ?&gt;&lt;/strong&gt;&lt;a href="&lt;?php echo $this-&gt;getUrl('') ?&gt;" title="&lt;?php echo $this-&gt;getLogoAlt() ?&gt;" class="logo"&gt;&lt;img src="&lt;?php echo $this-&gt;getLogoSrc() ?&gt;" alt="&lt;?php echo $this-&gt;getLogoAlt() ?&gt;" /&gt;&lt;/a&gt;&lt;/h1&gt;
          &lt;?php else:?&gt;
          &lt;a href="&lt;?php echo $this-&gt;getUrl('') ?&gt;" title="&lt;?php echo $this-&gt;getLogoAlt() ?&gt;" class="logo"&gt;&lt;strong&gt;&lt;?php echo $this-&gt;getLogoAlt() ?&gt;&lt;/strong&gt;&lt;img src="&lt;?php echo $this-&gt;getLogoSrc() ?&gt;" alt="&lt;?php echo $this-&gt;getLogoAlt() ?&gt;" /&gt;&lt;/a&gt;
          &lt;?php endif?&gt;
          &lt;div class="quick-access"&gt;
              &lt;?php echo $this-&gt;getChildHtml('topSearch') ?&gt;
              &lt;p class="welcome-msg"&gt;&lt;?php echo $this-&gt;getWelcome() ?&gt; &lt;?php echo $this-&gt;getAdditionalHtml() ?&gt;&lt;/p&gt;
              &lt;?php echo $this-&gt;getChildHtml('topLinks') ?&gt;
              &lt;?php echo $this-&gt;getChildHtml('store_language') ?&gt;
          &lt;/div&gt;
          &lt;?php echo $this-&gt;getChildHtml('topContainer'); ?&gt;
      &lt;/div&gt;
  &lt;/div&gt;
  &lt;?php echo $this-&gt;getChildHtml('topMenu') ?&gt;
  </code></pre>
  
  <p>I cannot understand why the topSearch block is being loaded even if it is not declared in the header in page.xml as a child of header.</p>
  
  <p>Could anyone explain? Thanks!</p>