Northwest Airlines Corp. was a major airline in the United States from 1926 until its merger with Delta Air Lines in 2010. The merger made Delta the largest airline in the world until the American Airlines–US Airways merger in 2013.

Delta Air Lines is one of the major airlines of the United States and a legacy carrier headquartered in Atlanta, Georgia. The United States' oldest operating airline and the seventh-oldest operating worldwide, Delta along with its subsidiaries and regional affiliates, including Delta Connection, operates over 5,400 flights daily and serves 325 destinations in 52 countries on six continents. Delta is a founding member of the SkyTeam airline alliance. As of the end of 2022, it had 90,000 employees.