Hovering over the marker will display the name of the element, the number of clicks the element has received and outline the element's position on the page. Clicking on a marker will reveal additional click information about the element.
There are three views for the Overlay report. The default view is the Live view; in addition to the Live view, there is the Other view and Both view.
Clicks to live elements will show under the Live view. Links, buttons, text fields, etc; these are all considered live elements. The Other view will display clicks to non-live elements like paragraphs, divs, spans, etc; any element that does not results in an action when clicked. Markers for the Other view will always be colored with a shade of grey.** Lastly, Both will show Live and Other elements at the same time.
*Red and blue markers colors are only used for the Live view.
**Grey markers are only used for the Other view.