ot_typo3/ot_templating/Resources/Private/Layouts/Classic/3Col.html

<f:comment><!-- base layout for a page, with header, carousel, navbar, breadcrumb and footer --></f:comment>
<f:layout name="3Col" />

<f:comment><!-- Render the header defined in partial/header.html--></f:comment>
<f:render partial="Classic/Header" arguments="{_all}" />

<div class="main">
    <f:comment><!-- Left column --></f:comment>
    <div class="leftcol">
        <div class="content">
            <f:comment><!-- render the content of the leftcol section (left column) --></f:comment>
            <f:render section="Leftcol" />
        </div>
    </div>

    <f:comment><!-- Central column --></f:comment>
    <div class="centralcol">
        <div class="content">
            <f:comment><!-- render the content of the content section (middle column) --></f:comment>
            <f:render section="Content" />
        </div>
    </div>

    <f:comment><!-- Right column --></f:comment>
    <div class="rightcol">
        <div class="content">
            <f:comment><!-- render the content of the rightcol section (right column) --></f:comment>
            <f:render section="Rightcol" />
        </div>
    </div>

</div> <!-- /container -->

<f:comment><!-- Render the footer defined in partial/footer.html--></f:comment>
<f:render partial="Classic/Footer" />