Ridesharing is where you use an app to request a ride, a nearby driver of that company will pick you up and take you to your destination. The cost is much less than a cab and tipping is not expected (and with some not even possible).
It is dominated by two companies: Lyft and Uber. There are other ones, but these are the biggest and naturally you do want to use a company that has a lot of drivers in your area so the wait time is less. We used Lyft first, but ran into some issues with the app and found out the customer service isn't the best so we switched to Uber.
It's a really great option for people that don't have a car, or their car is being worked on, and now I think especially for when you are on vacation. (Many people also use it as their designated driver so you can go bar hopping and all your friends can drink!) It's simple to use and what's really great is you don't actually deal with any money with the drivers, it's all paid electronically through the app so it's much faster!
If you're interested, take a look at what ridesharing companies are strong in your area, or the area you are visiting. But I'd recommend Uber.
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