Dragons are a staple of the fantasy genre. They are found in many high fantasy series such as Lord of the Rings, Dragonriders of Pern, The Inheritance Cycle, and even in the Kingkiller Chronicles by Patrick Rothfuss. I also use dragons in many of the stories I write. The name I use on my blog (ecladragon) actually comes from one of my first characters from a major project named Ecla who had the power to turn into a dragon.
In my own stories I tend to portray dragons as misunderstood creatures who are feared. I have also used them to signify leadership and in one of my newer projects dragons are non sentient creatures. The misunderstood aspect is what is important here. I use the typical western appearance for my dragons. Large, scaly creatures with bat-like wings, long necks, claws, and teeth, and four legs. They are wise but only as wise as the wisest human. Also though I rarely ever write dragons this way, the dragons in my worlds are not always wise.
Dragons are feared because of course they breath fire and eat people. They are dangerous. They are also greedy and will burn down whole villages to get at shiny things which they will then take back to their spacious caves. They are often seen resting on top of piles of gold and other precious objects. This is the typical description of a western dragon in fiction. If I were to describe an eastern dragon it would be that they are wise snake-like creatures with two clawed hands, a body part based off of each of the chinese zodiac animals, and are extremely powerful.
The thing is that though you should always use an existing description as inspiration, you don’t have to always use any creature from the real world, real or fictional. Make the creatures your own. It is interesting to see how other people write dragons into their stories. Sometimes they are rooted in real-life mythologies, sometimes they come directly from the mind of the writer.