Which Delta Air Lines Planes Have Special Liveries & Why?

Delta Air Lines is one of the largest and most well-known carriers in all of aviation, and, while simple, its mainline livery is effective and recognizable. Indeed, the red logo and dark blue accents are more than enough for most people to identify an aircraft as belonging to Delta, even at a short glance. However, the airline has also painted certain aircraft in more colorful liveries to support various causes.