title: Create subheaders in table with javascript
body: <p>I would like to know how to create sub-header columns by only using javascript. My data is coming from server so I just want to create columns and subheaders. </p>
  
  <p>So columns I have already created but how to have subheader with only javascript ( css can be there) but not with the help of html that I am not able to get.
  <a href="https://i.stack.imgur.com/Xeud0.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Xeud0.png" alt="Like this"></a></p>
  
  <p>Can someone help me with this.
  this is some demo of table -</p>
  
  <p><a href="https://i.stack.imgur.com/XJcPc.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/XJcPc.png" alt="enter image description here"></a></p>
  
  <p>here at top I need to add two subheader with 3 columns</p>