Format strings vs concatenation : <p>I see many people using format strings like this:</p>

<pre><code>root = "sample"
output = "output"
path = "{}/{}".format(root, output)
</code></pre>

<p>Instead of simply concatenating strings like this:</p>

<pre><code>path = root + '/' + output
</code></pre>

<p>Do format strings have better performance or is this just for looks?</p>
