Semantic UI is an open-source framework that uses CSS and jQuery to build great user interfaces. It is same as a bootstrap for use and has great different elements to use to make your website look more amazing. It uses a class to add CSS to the elements.
A label can be really useful to make your website more user-friendly.
Example 1: This example create a simple label content.
You can use any icon for example mail or any icon, you can check icons on the semantic-UI site.
Example 2: This example create a label for your form element.
Example 3: This example create a Floating Label.