Hidden city ticketing (aka “Skiplagging”) is when you book a longer route but leave the plane at the layover city because it’s cheaper. Example: Book New York → Dallas → Denver, but exit in Dallas. While it can save big money, it comes with risks. Airlines frown upon it, and frequent use can get accounts flagged. You also can’t check luggage since it will fly to the final city.
Bottom line: Hidden city ticketing works for one-off trips with carry-on bags, but don’t use it regularly if you want to keep your loyalty points and status.