How do I make an HTML button not reload the page

there is no need to js or jquery. to stop page reloading just specify the button type as 'button'. if you dont specify the button type, browser will set it to 'reset' or 'submit' witch cause to page reload.

 <button type='button'>submit</button> 

Use either the <button> element or use an <input type="button"/>.

In HTML:

<form onsubmit="return false">
</form>

in order to avoid refresh at all "buttons", even with onclick assigned.

You could add a click handler on the button with jQuery and do return false.

$("input[type='submit']").click(function() { return false; });

or

$("form").submit(function() { return false; });