***The information posted below is for entertainment uses only. It was researched on the Internet and not written by me and is not necessarily 100 percent accurate.  Thank you.***

Exactly -what- is a dragon? Exactly how many types of dragons exist? What is the difference between Western dragons and Eastern? This page briefly covers some of the dragon subspecies, from the Western Dragon to the Wyvern to the Drake. I hope you take the time to read at least some of this and learn a thing or two! It's really very interesting.

The dragon is a homoeothermic reptile. In other words, he is a warm-blooded creature and his body temperature is controlled internally. This characteristic enables him to adapt to the different climates of his very extensive habitat and to maintain his activities both day and night throughout the year, as he is not dependent on the warmth from the sun like the other reptiles. The dragon generally has wings, and his bones are hollow, enabling flight.

Skeleton

To maintain his enormous bulk in the air, his physical structure has had to be different from that of other reptiles whom many persons inaccurately associate dragon with these.
His wing bones fit on to broad shoulders, which support the powerful wing muscles; these require an extraordinary articulator system unknown in other species. The bones were tougher than reinforced concrete and much lighter.
It is important to note that the bones of a dragon are hollow like bird reducing their mass, scientifically: any creature with the physiology of a dragon can flight well and at great speed.
The Western dragon Eudraco magnificus occidentalis has a sturdy skeleton structure; large head, long neck, broad shoulders, thick legs, strong tail, and very large wings. The dragon's bones are very strong, but hollow and light. A dragon's jaw is large to accommodate the very strong muscles around it. The dragon is able to dislocate its jaw, as some snakes are able to do, and grab large objects. A dragon is an omnivore, or eats both plants and meat, and thus has two sets of teeth. The canine and incisor teeth are long and razor sharp, but there are also molars to chew their food instead of eating it whole.
The shoulder bones are thick to handle the large wing muscles needed to fly. The wing "finger" bones are very long, enabling the thin flight membrane to wrap tightly around them. There are many species of Western dragons, and this is only one example showing the different bones of the skeletal system.
The Oriental (or Eastern) dragon Dracoserpens Lung orientalis has an extremely long, thin skeleton structure. It has a medium sized head, very long neck, short legs, small hips, and a long tail. This skeleton is very maneuverable and flexible because of the shape, very much akin to that of a snake’s. This type of dragon does not have hollow bones, and the dragon's skeleton is thin because it doesn't need the mass to accommodate flight muscles. This dragon does not have any type of wings; it flies with magic verses brute strength.

Muscle

Western dragons have many more muscles then their Eastern cousins. This is mainly due to their massive flight muscles that have to lift their weight into the sky with the thrust of their wings. The main wing muscles are the Supraspinatus and Flexor alae major. Notice that the actual wing does not have many major muscles; it is all near the chest area. Other large muscles account for a very strong tail, and rear legs. The Western dragon could easily hold a human male's weight while in flight. The large jaw muscle Masseter, this muscle can easily crush bones.

Wing Structure

The dragon wing is a huge, leathery appendage that is found on several different species of dragon. The wing is usually larger than the dragon's body to accommodate the incredible force needed to lift and maintain flight.

Wing Bones

The wings of a dragon are based on the principle arm of any animal. If you look at the skeleton of a dragon front arm and claws, you will notice that the wing is just a very stretched out version. The two thick arm bones run from the body of the dragon, attaching itself with cartilage and muscle to an "elbow" of the wing. There are usually four or five elongated "fingers" on a wing, each ending in a claw or wingspike. One short "thumb" claw is at the "wrist.” The "fingers" then attach themselves to the "wrist joints", thus forming the complete wing.
For example, they consist of four lengthened fingers, the whole connected with a membrane as observed in the bat. It is significant to understand that the similar structure between the shoulder, the arm and the hand is homologous, (similar to that of its ancestors and descendents) with the corresponding structures of the wing for the dragon.

How do they fly?

The actual force of flight is the continuous down sweep of powerful wings scooping and thrusting the body upwards. Many immature dragons do not have the strength needed for a vertical jump from flat ground to take off. They will usually stay near higher cliffs to use the heat updrafts to keep aloft. It takes experience and conditioning to build the extremely strong flight muscles needed to lift the dragon body from the ground. Many dragons that have wings that are too small for them to fly adequately use a magical means to help them out. This magic helps keep dragons from straining themselves during long flights.

Wings Used as Weapons

Dragons can also use their wings as an attack weapon if need be, but this is often a last resort. The wing membranes are easily damaged compared to the rest of a dragon body. If a dragon wing membrane is slashed, it takes a very long time to heal, and there is a chance the dragon might never fly again if it does not heal correctly. If attacked on the ground, the dragon will usually run then jump in the air and fly off avoiding the attacker only to dive-bomb the enemy. But if a dragon is trapped on the ground, it often will tuck its wings tightly against its body and use its breath weapon and claws to protect itself. One of the many methods of wing attacks are that it will scoop down and slash with its razor sharp wing claws to immobilize the attacker.

Breath Weapon

Fire.
The thing that makes the dragon most feared. It's a hellish belch of flame that can turn flesh and bone into ash. But not all dragons breathe fire. Some have a freezing cold breath, others have acid, while some expel a deadly mist that can cause a myriad of damages. Some even have combinations of fire and acid, acid and frozen breath, etc.

HOW DO THEY BREATH FIRE?

It all starts when the dragon catch their prey. When dragons eat, they digest the food in a regular stomach. The digestion then continues in a second stomach that breaks down the food even further. After the dragon's body has used all it can from the second digestion, the body then turns the leftover food and acid into a byproduct of hydrogen. The dragon can hold the hydrogen in various large glands in its body for later use, and can call upon it at any time it needs to. When the dragon needs to belch its flame, the glands release the hydrogen into the lungs where it mixes with other various chemicals the body creates. Once this mixture finds oxygen, it burns extremely hot and very quick. This explanation is virtually same for dragons that breathe other types of breath. Their bodies just break down food into different compounds.

Physical Appearances

A dragon can be a huge creature, depending on the breed. One type of dragon has extremely small ears, large eyes, spines down its back, and a bone-type spade at the end of its tail. All dragon breeds are different. Some have long ears, and no spade, and some have a fleshy-type triangle-shaped spade. Some dragons do not have scales, but tough leathery skin, though most dragons have scales of some sort.

Color

The genes of the parent dragons determine Scale color. Usually only red dragons will mate with other red dragons, blue with blue, etc. But if a mating took place between a gold and a green dragon, the result might be a golden-green colored offspring, each dracling with more green than gold or vice versa, or have even amounts of both colors.
Scales on a dragon are never simply one shade of color. If a dragon is blue, there will be many, many shades of blue. Light, medium, dark, blue-black, etc. Scales are bright and shiny in a healthy dragon, but dull and muted if a dragon is ill.

Camouflage

In some breeds of dragons when the dragon is mature, the cells in the scales are able to change color such as a chameleon due to chromatophore, the pigment cells in the scales. This reaction can be caused by emotion (anger, happiness, etc) or by the sheer willpower. If a dragon is angered, it can change from its original color to a bright, fierce color such as red, to look more intimidating. Or during mating rituals, it can flow certain color patterns on its body to attract other dragons. Since dragons are extremely intelligent, it can choose which colors to change into to match the exact background it is near—including subtle shadow and depth perceptions.

A DRAGON'S ARMOR

The main function of scales is protection of the soft skin tissue of the dragon. An adult dragon can easily take a direct blow from a knight's sword and hardly flinch. The pattern of the body scales is a flat, rotating design that overlaps each other. Easy movement is due to the unique depression on the top side of each scale that allows them to lay evenly flat on the body. Of course, the dragon’s scale shape, texture, color, etc depends on the species and gender.

The scales on the chest area are the largest. The chest scales are, more often than not, shaped differently than a regular scale. The differences, once again, depend on the species and gender. The pattern of the chest scales overlaps, running from the throat to the stomach area to the end of the tail. All of the scales lightly slide over each other, so when a dragon walks it often makes a soft scraping sound. The overlapping scales make it difficult for anything to successfully injure a dragon.
Dragons can make their scales stand on end for washing as well as other things. Also, when angered, a dragon can puff up, spread its scales, and look a lot larger than the dragon actually is. Lifting the scales is also an effective heat reducing element. Making the scales stand on end allows the skin underneath to release heat, thus cooling the large animal down quickly.

The Draconic Senses

Dragons have the same senses as humans; sight, hearing, smelling, touch, and taste. Their regular five senses are incredibly sensitive. For example, the sense of smell is about 100 times more sensitive than a bloodhound dog. They can smell and hear a person or animal from several miles away!

Many dragons even have a six sense which is being able to "read" the emotion of another being.
Their six senses are very accurate at close range. If a person or animal is feeling a strong emotion, such as fear or hate, it will register very strongly to the dragon, even if it is not in visual range of it. This is where dragonfear comes from. Dragonfear is an all encompassing, frozen-in-place fear that the dragon causes upon the animal or person seeing a dragon. With several species, the “vicitims” don’t even have to be able to see the dragon yet still suffer from the dragonfear. Dragons sometimes use this advantage to beat its foes. Only few of the very bravest (or very dim-witted) are not affected by this terrible fear. In a friendly dragon, such as the Faerie Dragon, this aura is almost non-existent.
In theory, a dragon can also emit other emotions very strongly, such as euphoria (happiness), jealousy, etc.

Eastern Dragons

They have sinuous, serpentine bodies, four legs. They don't usually breath fire, and are usually shown without wings. The Adult Imperial Dragon is sometimes shown with wings. The dragons are said to be made up of many different types of animals of the Earth: the body of a snake, scales of a carp, head of a camel, horns of a giant stag, the eyes of a hare, ears like a bull, a neck like an iguana, belly of a frog, paws like a tigers, and claws like an eagle. Most of the time they are shown to have a lion-likemane around their necks, on their chins, and on each elbow. They have two antler-like horns decorating their wide-mouthed head, and two long whiskers spreading out from their snout. Eastern dragons have 117 scales, 81 infused with yang--the good--and 36 infused with yin--the bad. This evens out the dragons temper and personality.
There are three families of Eastern dragons: three toed, four toed, and five toed. Three toed dragons are Japanese; four toed dragons are Indonesian or Korean; five toed dragons are Chinese. They are shown in the colors blue, black, white, red, or yellow. Oriental dragons are usually shown with a pearl in their mouth, under their chin, or in their claws. This is apparently where the dragon gets its power and how it ascends to heaven. Roasted swallows are the Chinese dragon's favorite food.

Western Dragons

Western Dragons are thick, long bodied and have scaly skin, four strong legs, two bat-like wings, wedge-shaped heads, and long necks. They usually are portrayed as breathing fire. Some breeds of these dragons have been known to be shape changers, and others have the chameleon power to change color of their background. They are sometimes displayed as having a spade or spiked tail. They eat but once a month on a sheep or ox, or even a human (myth says they prefer virgin maidens). They can be any color, or many colors, depending on the breed of the dragon.

When most people think "dragon" they most likely think of the Western dragon. Western dragons are usually portrayed as evil, mean, and bloodthirsty. They were also known to have huge hoards of gold and jewels hidden in their lairs. The most famous dragons are portrayed as Western-type dragons: St. George and the Dragon, Beowulf and the Dragon, and Draco in the movie DragonHeart. Some stories have the western dragon as the Devil in Christianity. Other stories in legend say that eating a dragons' heart will give the consumer the power of understanding birds, eating the dragons' tongue enables the person to win any argument, and rubbing the dragons' blood on skin will protect against stab wounds. Another myth references Vlad Drakul to mean Son of the Dragon, or Devil. The end of the dragon came with Christianity, and knights that were eager to prove their faith. The knights quickly discovered that dragon-hunting was very profitable, and soon most the dragons in the world were destroyed in a very short time. Vikings had dragon figureheads on the prow of their ships. The dragons on the ships were believed to endow keen sight and cunning to the Viking warriors. Today the Welsh flag still has a red dragon on a green/white background, and the red dragon is their national symbol.

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