For those who don't know about it or those who don't know the extent of it. The majority of Scotland is covered. It is handy for checking if places are easy to get to or even worth the trip, scenery wise. I use it to check complicated junctions there's nothing worse than a missed turn on a busy road. I used it to help Hunterston visitors find their way from Edinburgh / Glasgow station or even Greenock docks. If you are touring you can check out e.g. Loch Ness to see if you have the time to get there. You can even see inside Stirling castle to help decide whether to go.
I also recommend RAC route planner for realistic distances, routes and travelling times.
Quite a hot topic lately. You can see the train bridge on the left and the new one under construction on the right.
You can work out if things are worth including in your itinerary depending on time available, weather or entrance fees.