
An MDL badge component is an onscreen notification which can be a number or an icon. It is generally used to emphasize the number of items.
MDL provides a range of CSS classes to apply various predefined visual and behavioral enhancements to the badges. The following table lists down the available classes and their effects.
| Sr.No. | Class Name & Description | 
|---|---|
| 1 | mdl-badge Identifies element as an MDL badge component. Required for span or link element.  | 
| 2 | mdl-badge--no-background Applies open-circle effect to badge and is optional.  | 
| 3 | mdl-badge--overlap Makes the badge overlap with its container and is optional.  | 
| 4 | data-badge="value" Assigns a string value to badge used as attribute; required on span or link.  | 
The following example will help you understand the use of the mdl-badge class to add notifications to span and link elements.
The MDL classes given below will be used in this example.
mdl-badge − Identifies element as an MDL badge component.
data-badge − Assigns a string value to badge. Icons can be assigned to it using HTML symbols.
<html>
   <head>
      <script src = "https://storage.googleapis.com/code.getmdl.io/1.0.6/material.min.js">
      </script>
      
      <link rel = "stylesheet" 
         href = "https://storage.googleapis.com/code.getmdl.io/1.0.6/material.indigo-pink.min.css">
      <link rel = "stylesheet" 
         href = "https://fonts.googleapis.com/icon?family=Material+Icons">
      <style>
         body {
            padding: 20px;
            background: #fafafa;
            position: relative;
         }
      </style>
   </head>
   
   <body>
      <span class = "material-icons mdl-badge" data-badge = "1">account_box</span>    
      <span class = "material-icons mdl-badge" data-badge = "★">account_box</span>	
      <span class = "mdl-badge" data-badge = "4">Unread Messages</span>
      <span class = "mdl-badge" data-badge = "⚑">Rating</span>
      <a href = "#" class = "mdl-badge" data-badge = "5">Inbox</a>
   </body>
</html>
Verify the result.