The difference between "United" and "Polaris" is that United is the airline brand, while Polaris is the name of its specific "international long-haul business class" product. You don't "fly Polaris" as a separate airline; rather, you book a Polaris seat on a United-operated flight. Polaris was designed to revolutionize the "sleep-to-destination" experience, featuring lie-flat pods with direct aisle access, Saks Fifth Avenue bedding, and multi-course dining. If you are flying domestically within the U.S. or on short-haul international flights (like to Canada or Mexico), you will likely be in "United First" or "United Business," which offer wider seats but not the full lie-flat Polaris experience. Furthermore, "Polaris" also refers to the exclusive United Polaris Lounges found at major hubs like Newark, SFO, and Chicago; these lounges are strictly reserved for passengers traveling in a Polaris pod and offer a much higher level of luxury—including sit-down restaurant service and shower suites—compared to the standard "United Club" lounges that are open to a wider range of members and status holders.