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copied!<p>The advantages of object and array literals over using the respective constructors are:</p> <ul> <li>Shorter and more readable</li> <li>Safer: literals will still work when the <code>Array</code> or <code>Object</code> constructors have been overridden</li> <li>Possibly faster, though it's unlikely to be a major consideration (any bottlenecks will almost certainly originate elsewhere in code)</li> </ul> <p>In the case of arrays, there's an additional advantage of a literal: it's impossible to create an array with a single member using the <code>Array</code> constructor alone. For example, <code>[3]</code> will create an array with one element which is the number 3, while <code>new Array(3)</code> creates an array of length 3.</p> <p><strong>Update: the following paragraph is no longer relevant now the question has been edited.</strong></p> <p>Regarding Booleans, you seem to have a misconception: <code>new Boolean(false)</code> is not the same as <code>false</code>. The <code>Boolean()</code> constructor creates a Boolean object whereas <code>false</code> and <code>true</code> are Boolean primitives. In fact, <code>new Boolean(false)</code> evaluates to <code>true</code> when coerced into a Boolean in, for example, an <code>if</code> statement. In short, there's very rarely a reason to use the <code>Boolean()</code> constructor. Use <code>true</code> and <code>false</code> instead. Similarly, other primitives such as strings and numbers have corresponding <code>String()</code> and <code>Number()</code> constructors that produce <code>String</code> and <code>Number</code> objects that are different to primitive strings and numbers and should generally be avoided.</p>

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