Thousands of travelers were stranded at U.S. airports Wednesday due to an hours-long computer outage.

More than 1,000 U.S. flights were cancelled early in the day and almost 7,000 flights were delayed, according to the tracking site FlightAware.

Staying calm __ and knowing your rights __ can go a long way if your flight plans are disrupted, experts say. Here’s some of their advice for dealing with a flight delay or cancellation:

MY FLIGHT WAS CANCELED. WHAT NEXT?

If you still want to get to your destination, most airlines will rebook you for free on the next available flight as long as it has seats, according to the U.S. Department of Transportation.

If you want to cancel the trip, you are entitled to a full refund, even if you bought non-refundable tickets. You’re also entitled to a refund of any bag fees, seat upgrades or other extras.

Kurt Ebenhoch, a consumer travel advocate and former airline executive, stressed that travelers are eligible for a refund, not just vouchers for future travel. If you do take a voucher, make sure you inquire about blackout dates and other restrictions on its use.

MY FLIGHT WAS DELAYED. DOES THE AIRLINE HAVE TO PROVIDE ME WITH COMPENSATION?

No. There are no federal laws requiring airlines to provide passengers with meal vouchers or other compensation when their flights are delayed. But each airline has its own policy, so if you are experiencing a long delay, you should ask if you can get a meal voucher or a hotel room.

MY FLIGHT WAS DELAYED FOR SO LONG THAT I NO LONGER WANT TO MAKE THE TRIP. CAN I GET A REFUND?

Maybe. The U.S. Department of Transportation says travelers are entitled to a refund if there is a “significant delay,” but it does not define “significant.” The refund depends on many factors, including the length of the delay and the length of the flight. It’s decided on a case-by-case basis.

CAN I ASK TO BE BOOKED ON ANOTHER AIRLINE’S FLIGHT?

Yes. Airlines aren’t required to put you on another airline’s flight, but they can and sometimes do, according to the DOT. Jeff Klee, CEO of CheapAir.com, recommends researching alternate flights while you’re waiting to talk to an agent. Agents are typically under a lot of pressure when a flight is canceled, so giving them some options helps.

Ebenhoch also suggests looking for alternative airports that are close to your original destination.

I’M FACING A LONG WAIT TO REBOOK MY FLIGHT. WHAT SHOULD I DO?

If someone in your traveling party is at a higher level in a frequent flier program, use the number reserved for that level to call the airline, Ebenhoch said. You can also try calling an international help desk for the airline, since those agents have the ability to make changes.

HOW CAN I AVOID THIS IN THE FUTURE?

Ebenhoch said nonstop flights and morning flights are generally the most reliable if you can book them. If you’re worried about making it to the airport in time for a morning flight, he said, consider staying at a hotel connected to the airport the night before.

Klee recommends comparing airlines’ policies on the DOT’s service dashboard: https://www.transportation.gov/airconsumer/airline-customer-service-dashboard. He also suggests reserving multiple flights and then canceling the ones you don’t use, as long as the airline will refund your money or convert it into a credit for a future flight.