Rolex 24 at Daytona features 4 classes of cars. What does each mean?

Can't tell the two prototype classes apart at Daytona's Rolex 24? Or the two GTD classes? If all else fails, find the color scheme.
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10 Of The Best-Looking American Race Cars Ever Made

For over a century, Motorsport has been deeply rooted in the legacy of the American automotive industry. Many major manufacturers that helped put the nation on the map for racing provided us with some ...
Jalopnik

Here Are The Weirdest Cars Racing In The Nürburgring 24 Hours This Year

The ADAC Ravenol 24H Nürburgring is among the strangest endurance sports car races in the world with multi-class action on the longest and twistiest race course anywhere. Part of what makes this race ...
Motor Authority

BMW's new M2 race car tests hard at the 'Ring

BMW is working on a new generation of its entry-level customer race car based on the M2 coupe, and prototypes are currently being evaluated, including in the grueling races of the Nürburgring ...