'tram', 'trolley', 'trolleybus', 'trackless trolley'.

Please have a look at this and confirm if I am right or not:
1/ ‘trolley’ (AmE) and ‘tram’ (BrE) mean the same - a public vehicle running on tracks and powered by electricity
2/ ‘trolleybus’ (BrE) and ‘trackless trolley’ (AmE) - a public vehicle not running on tracks but having a wire on its top to collect electricity on the roads.

Be the way, I don’t understand ‘collect electricity’ on the road’ very well. How can there be electricity on the roads to collect? :roll:

Please help.
Many thanks,

I can’t think of anywhere in the US where you’ll find someone referring to a “trackless trolley” and we have few “trolleys” at all. I’d be willing to be that most Americans wouldn’t requrie a trolley to use electricity to call it a trolley. We’d call it a “a little train-thing that runs on tracks.”