KLM, Air France, Alaska Airlines, V Australia, Air Nigeria, China Airlines, Hawaiian Airlines, Alitalia, Olympic Air, American Eagle, and other SkyTeam members.
Questions of this nature are always a matter of opinion. However, Delta has improved greatly in customer service and products offered through the past couple years, due to a $2 billion investment ....
The main agreements are with Air-France-KLM-Alaska. There are other SkyTeam partners too. These are Aeroflot, Czech Airlines, Korean Air, AeroMexico, Alitalia, Tarom, Air Europa, China Southern,...
The company was named Delta Air Services in 1928 (long before Delta winged aircraft). They were based in Monroe LA, and the name is probably linked to the Mississippi Delta region of LA.