What are Pure HTML export buttons in jQuery Data Table?

jQuery Data Table provides export buttons with the help of which we can make a structure like the following −

• Export PDF
• Export CSV
• Export HTML
• Export Excel

For this, we need to write code −

var tbl = $('#extable').DataTable({  
   dom: 'export',    
   buttons: [      
   {          
      extend: 'collection',          
      text: 'Export',          
      buttons: [ 'csvHtml5', ' pdfHtml5', 'copyHtml5', 'excelHtml5' ]      
   }    
   ]
});