How to add <li> using javascript?

Question

I want to add one more li at last but using JavaScript/jQuery

for example i want to add this li at last <li><a href="#header" >Back to top</a></li>

<ul id="nav">
    <li><a href="#nowhere" >Lorem</a></li>
    <li><a href="#nowhere" >Aliquam</a></li>
    <li><a href="#nowhere" >Morbi</a></li>
    <li><a href="#nowhere" >Praesent</a></li>
    <li><a href="#nowhere" >Pellentesque</a></li>
        Here i want to add one more li using javascript
</ul>

Answer 1

$(document).ready( function(){
    $('ul#nav').append('<li><a href="#header">Back to top</a></li>');
}  

Answer 2

Use the append function.

$("#nav").append('<li><a href="#header">Back to top</a></li>');