LOS ANGELES — First, Uber framed itself as an alternative to taxis. Now the San Francisco ride-hailing company is rolling out a new service that sounds kind of like a bus.

The ride-hailing company is introducing Express Pool to several cities this week. It’s a lower-cost service for passengers who are willing to share rides with strangers and begin and end their journeys at specified pickup and drop-off locations.

Similar to Uber’s communal Pool service, customers book Express Pool rides using Uber’s mobile app and are matched with other passengers traveling the same direction. But instead of offering door-to-door pickup and drop-off, which can often lead to convoluted routes and backtracking, Express Pool directs passengers to walk to convenient spots and deposits them within a few blocks of their destination.

The result is a service that’s more affordable for passengers and more efficient for drivers, said Ethan Stock, Uber’s product lead on Express Pool.

By directing passengers to pickup locations, the company expects to cut down on travel time and make Uber rides more efficient.