Labels are just a simple Bootstrap component that you can include in your pages as needed. They represent one of many Bootstrap options you can include in your theme.

About labels

Labels might come in handy for adding button-like tags next to elements, such as POST, DELETE, UPDATE methods for endpoints. You can use any classes from Bootstrap in your content.

<span class="label label-default">Default</span>
<span class="label label-primary">Primary</span>
<span class="label label-success">Success</span>
<span class="label label-info">Info</span>
<span class="label label-warning">Warning</span>
<span class="label label-danger">Danger</span>

Default Primary Success Info Warning Danger

You can have a label appear within a heading simply by including the span tag in the heading. However, you can’t mix Markdown syntax with HTML, so you’d have to hard-code the heading ID for the auto-TOC to work.