 <p>It's a placeholder for formatting. It represents a string.</p> <pre><code>" %s link.get" % ('href') </code></pre> <p>is equivalent to</p> <pre><code>" " + 'href' + " link.get" </code></pre> <p>The placeholders can make things more readable, without cluttering the text with quotes and +. Though in this case, there is no variable, so it is simply</p> <pre><code>" href link.get" </code></pre> <p>However, <code>.format()</code> is preferred to <code>%</code> formatting nowadays, like</p> <pre><code>" {} link.get".format('href') </code></pre>