Mx Modals Joomla Module
Popup is a small (or not) window that displays some kind of information in it. Usually it is displayed over other content, like chart or map, but in general does not obstruct interactivity with it. E.g. you can still interact with the chart around the Popup.
There can be any number of popups displayed at any given time.
Modal is much more stricter. If there's a Modal open, you don't get to do anything with the chart until Modal is closed. There can be only one Modal at the same time.
Opening a Popup
It has the option to auto open a Popup and close it in time of your choice
Opening Popup on click
It open a Popup whenever user clicks on button.
Open multiple popups.