An event was held in Daley Plaza at 5:45 p.m. for the Divvy bike sharing program.
Starting Friday morning, members will be able to rent bikes, and then return them back to docking stations around the city.
Seventy-five bike docks are already in place, more are coming by August.
The launch was delayed two weeks to allow more time to test the system.
Memberships start at 75 dollars.
Twenty-four-hour passes will also be available.
