There are two groups of dragons: chromatic dragons and metallic dragons. I'm not just talking about color.

Chromatic dragons are black, blue, green, red, and white. These are the fierce dragons that tend to be more inclined towards evil (not to say they're all evil, but they sway that way). I personally still find chromatics fascinating and beautiful! Just don't get nearly as close.

Metallic dragons are brass, bronze, copper, gold, and silver. These dragons might not be naturally malevolent, but they need to be respected just as much (if not more, in some cases!), seeing as they're already doing you a favor by letting you live. Metallic dragons don't wish to fight, but they will if provoked.