class="header-section-number">4</span> Data Import and Relations</a></li>
<li><a class="" href="tidy.html"><span class="header-section-number">5</span> Data Tidying</a></li>
<li><a class="" href="wrangle.html"><span class="header-section-number">6</span> Data Wrangling</a></li>
<li><a class="" href="summary.html"><span class="header-section-number">7</span> Data Summaries</a></li>
<li><a class="" href="custom.html"><span class="header-section-number">8</span> Customising Visualisations</a></li>
<li><a class