On the Rome to Rio website when you input a starting point destination and the destination you are travelling to you, invariably you are presented with a train, a bus, and sometimes a combination of the two : a bus and train solution to travel between the two towns.
Sometimes another option is offered: rideshare which presumably is similar to different people sharing a taxi to a destination
eg Heathrow into central London.
Have experienced travellers and forum posters used this form of transportation?
There is a service called BlaBlaCar, but I have never used it.
Whenever I see the term "ride share", I always assume they're referring to Uber or Lyft. I've never encountered the situation of people sharing a Taxi (ie: from LHR into London), but I suppose it's possible.
Effectively it is organised hitchhiking. People going the same way, or part of it, as a driver.
When I was a kid we had notice boards with little cards at the university common rooms or in youth hostels. Now it is an app or several apps, or emails or whatsapps.
Everybody pays a part, and the driver provides the car.
What you don't know is anything about the driver, what he or she has been drinking or smoking, or their driving ability or insurance.
But it is cheap.
I'm a New Zealander who lived in Australia for a long time. It is quite common in Australia if you are waiting at a taxi rank at the airport, particularly after a few flights have landed at the same time, to find out if other travellers are going in the same direction and then pool the use of a taxi and perhaps pay a reduced fare.
And I could see how using a rideshare arrangement in Europe could be problematic. As one of the posters has pointed out you don't know what they have been imbibing prior to departure.