$ Not defined? :/

Question

<button>click</button>
<script>alert("commet")
$("button").on("click", function() { alert("comment" )
});

When i run the above code
an error message appears and it says that
$ is not defined

Answer 1

u dont have jquery lol
add this before your script tag
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>

Answer 2

It worked thanks c: