About 737 from Wikipedia:
The Boeing 737 is an American narrow-body airliner produced by Boeing at its Renton factory in Washington. Developed to supplement the Boeing 727 on short and thin routes, the twinjet retained the 707 fuselage width and six abreast seating but with two underwing Pratt & Whitney JT8D low-bypass turbofan engines. Envisioned in 1964, the initial 737-100 made its first flight in April 1967 and entered service in February 1968 with Lufthansa. The lengthened 737-200 entered service in April 1968, and evolved through four generations, offering several variants for 85 to 215 passengers.

The 737-100/200 original variants were powered by Pratt & Whitney JT8D low-bypass turbofan engines and offered seating for 85 to 130 passengers. Launched in 1980 and introduced in 1984, the 737 Classic -300/400/500 variants were upgraded with more fuel-efficient CFM56-3 high-bypass turbofans and offered 110 to 168 seats. Introduced in 1997, the 737 Next Generation (NG) -600/700/800/900 variants have updated CFM56-7 high-bypass turbofans, a larger wing and an upgraded glass cockpit, and seat 108 to 215 passengers. The latest generation, the 737 MAX -7/8/9/10 variants, powered by improved CFM LEAP-1B high-bypass turbofans and accommodating 138 to 204 people, entered service in 2017. Boeing Business Jet versions have been produced since the 737NG, as well as military models.

As of May 2024, 16,525 Boeing 737s have been ordered and 11,762 delivered. Initially, its main competitor was the McDonnell Douglas DC-9, followed by its MD-80/MD-90 derivatives. In 2013, the global 737 fleet had completed more than 184 million flights over 264 million block hours since its entry into service. It was the highest-selling commercial aircraft until being surpassed by the competing Airbus A320 family in October 2019, but maintains the record in total deliveries. The 737 MAX, designed to compete with the A320neo, was grounded worldwide between March 2019 and November 2020 following two fatal crashes. A further accident involving an uncontrolled decompression led to the grounding of most 737 MAX 9 aircraft in January 2024.

About Southwest airlines from Wikipedia:
Southwest Airlines Co. is a major airline in the United States that operates on a low-cost carrier model. It is headquartered in Love Field, Dallas, Texas, within the Dallas–Fort Worth metroplex, and has scheduled service to 121 destinations in the United States and ten additional countries.[4] As of 2018, Southwest carried more domestic passengers than any other United States airline.[5] It is currently the third largest airline in North America based on passengers flown.[6]

The airline was established on March 9, 1967,[7] by Herb Kelleher and Rollin King as Air Southwest Co. and adopted its current name, Southwest Airlines Co., in 1971, when it began operating as an intrastate airline wholly within the state of Texas, first flying between Dallas, Houston, and San Antonio.[8][9] It began regional interstate service in 1979, expanding nationwide in the following decades. Southwest currently serves airports in 42 states and multiple Central American destinations.

Southwest's business model is distinct from other US airlines as it uses a rolling hub and point-to-point network and allows free checked baggage. It exclusively uses Boeing 737 jets in its fleet.

The airline has nearly 66,100 employees and operates about 4,000 departures a day during peak travel season.[10][11]

The airline was established on March 9, 1967,[7] by Herb Kelleher and Rollin King as Air Southwest Co. and adopted its current name, Southwest Airlines Co., in 1971, when it began operating as an intrastate wholly within the s