Classes

This attribute helps in applying the same styles to all elements having the same class.  

Syntax:

.myclass {  background-color: black;   color: white;   font-family:verdana; } <tagname class="myclass">data</tagname>

CSS covers classes and styling related topics in brief. Here we have just given a basic example of giving class to HTML element. 

You can also add multiple class to one element by just adding a class with space in between them.