Beginning on Monday, roughly 6,000 bicycles will be available for public use at more than 300 stations in Manhattan below Central Park, and parts of Brooklyn. Anyone who is at least 16 can check out a bike from any station and return it to any other station in the city. Here are some answers to questions about the program, which is called Citi Bike.

Q.How much does it cost?

A. An annual membership costs $95 before tax, and allows riders to rent bikes for as long as 45 minutes with no additional charge. Access for one week costs $25, and a 24-hour pass is $9.95. In these instances, riders are allowed only 30 minutes of use before overtime fees start.

Q. What if I want to ride all day?

A. Because of the overtime charges, the program is best suited for short trips. Visitors or other riders seeking to use a bike for a full day, without having to check it back in, are likely to be better off with private rental companies. For example, the cost of 24-hour Citi Bike access and a three-hour rental would be $58.95 plus tax.

Q. Can I ride yet?

A. Only if you are an annual member who signed up by May 17. For everyone else, the system begins Sunday.

Q. How do I pay?

A. Credit or debit card. Annual memberships can only be bought online.

Q. How do I take the bike out of its dock?

A. Annual members are issued keys that can be inserted into slots at each bike dock. Weekly or daily riders are given a code to enter into a keypad. When the key is inserted or the code is entered, a green light should blink on. A rider can then remove the bike by lifting it from its seat with one hand and holding the handlebar with the other, then pulling the bike out.

Q. How do I return the bike?

A. Push the front wheel into the dock — this can require a vigorous shove — and wait for the green light to blink on. If it does, the trip has officially ended. If the light is yellow or red, try again.

Q. What if there are no available slots when I return the bike?

A. Riders can dip either their membership keys or their credit or debit cards into the kiosk and select “Request Time Credit” to add an extra 15 minutes to the trip, allowing riders to try their luck at a nearby station.

Q. What if I want to keep the bike?

A. If a bike is not returned within 24 hours, the system charges a rider’s credit or debit card a fee of up to $1,000.

Q. Are discounted memberships available?

A. Residents of public housing can receive annual memberships for $60.

Q. Are helmets required?

A. No. The city encourages their use, but officials say a requirement would discourage ridership.

Q. What if I crash?

A. Call 911. Within 24 hours of a crash, a rider must notify Citi Bike, by calling (855) 245-3311. The city also asks that riders with other problems, like malfunctioning software, call that telephone number.