Image mapping

Howdy ?? I’m creating image map and it work like this: https://www.northtexasdentists.com now, the only issue is sometime it takes to long before the image response, I mean the graphic doesn’t seem to behave very smoothly. I’m thinking of using this https://www.securityguardtraininghq.com, because it seems its behave smoothly :). But I don’t have idea how this thing work, I think its not using image map. Can someone tell me how this work? BTW I’m using offline installation right now, Thanks