Error: '$' is undefined Options

[Blueie]

Hello

I have the following JavaScript in my 'Home' page:

CODE

<script type="text/javascript">
    
$(function() {
      $("#lava_menu").lavaLamp({
        fx: "backout",
        speed: 700
      });
    });
  
</script>

and I am getting the following error:

Error: '$' is undefined

Please see attached.

What does that mean, please, and how may I correct it - the error pops up every time I go to that page.

Thank you.

Blue

[Christian J]

That looks like jQuery. Does the page embed the actual jQuery library as well?.