By default, the popup opens when you hover over a marker, and closes when you click on the map or hover over another marker. In the marker settings, you can also select the option for the popup to open when the user clicks on the marker.

In addition to hovering or clicking, you can also set the popup to automatically open after loading the map or set it to always be open.

On the demo map on this page, you can see examples of different popup opening behaviors.