A re-introduction to JavaScript
> You can also use the unary + operator to convert values to numbers:<p><pre><code>    + "42"; // 42
</code></pre>
> [...] However the "+" operator simply converts the string to NaN if there is any invalid character in it.<p>Being a bit pedantic here, why not recommending the Number function which may be less obscure for beginners?<p><pre><code>    Number("42"); // 42</code></pre>