t-are-keys">What are keys</a></h3>
<p>Keys are a mechanism that allows re-ordering DOM elements within a NodeList, and mapping specific data items in a list to the respective DOM elements that are derived from them, as the data items move within the list.</p>
<p>In other words, a <code>key</code> is a way of saying &quot;this DOM element is for the data object with this id&quot;.</p>
<p>Typically, a <code>key</code> property should be the unique identifier field of the objects in the data array.</p>
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