A hotspot is the common name for a Wi-Fi network's access point.
A public hotspot is usually hosted by a campground, marina, cafe or library.
A private hotspot might be one you host yourself, or one you've been given special access to such as a driveway host or business you are visiting.
A mobile hotspot or personal hotspot is the term often used to describe a private hotspot made by a smartphone or mobile hotspot device to share a cellular connection.