When you hear the word "dragon," the first thing that would most likely come to your mind is that of a winged, fire-breathing monster. (Oriental dragons don't have wings but can still fly). Whether one is an invaluable ally or an enemy that must be put to the sword depends on the plot of the book or movie you are enjoying at the moment.
In real life, however, the closest you'll get to a dragon is the Komodo dragon, which thrives in select coastal areas of Indonesia's Lesser Sunda. At more than 300 pounds, it's the heaviest lizard on Earth. Like fictional dragons, Komodo dragons can devour animals and humans. Unlike fictional dragons, however, they can't breathe fire.
At best, dragons are brainchildren of ancient culture, dating back to the ancient Sumerians and Greeks. In fact, the Sumerians are believed to have introduced the staple fiction adventure plot of slaying dragons, through the story of Kur, the Sumerian equivalent of Hades. As the myth goes, the dragon Kur abducted the goddess Ereshkigal (ancient Sumer's Persephone), only to be slain at the hands of Enki, the Sumerian god of water.
This ancient theme would eventually be adopted in almost every sci-fi or fantasy plot involving these flying flamethrowers, spawning versions like Tiamat and Leviathan, which avid gamers would associate with the Final Fantasy multiverse. You can watch free movies online about these mystical creatures, and keep the myth of the dragon alive.