AIS was created to give vessel operators the ability to gather and distribute electronic navigational data to other mariners. Including those requiring navigational data to those who are out of visual range, and geographic obstructions in their navigational path.
Imagine a modern ship radar or an electronic charts display or plotter that includes a simple capacity for every significant ship for every important ship within VHF radio range.
Each is designed with a velocity detector indicating speed, size of the ship, position, link to GPS, or differential GPS accuracy. By pointing and clicking on a ship symbol, you can see the ship name, course, call sign, and registration number.
Historical ships can be plotted, as well as additional navigational information. These can all be available.
Before it was only available to modern vessel traffic service operation centers can now be available to virtually all ships, whether personal or commercial.