Psoriasis is a common disease of the skin. It is caused when the immune system sends out false information to the growth cells and speeds up the process of the skins growth. There are five different types of Psoriasis, but because it is not an infection, it is not contagious. The five various types of Psoriasis are: Plaque Psoriasis, Guttate Psoriasis, Pustular Psoriasis, Inverse Psoriasis, and Erythrodermic Psoriasis. Psoriasis is also a chronic disorder, meaning that it stays around for quiet a while, it may appear to disappear, but it can come back.
Ferdinand Ritter von Hebra
Ferdinand von Hebra was an Austrian Physician and Dermatologist. He graduated in 1841 from the university of Vienna with a degree in Medicine. He was also the author of the atlas: Lehrbuch der Hautkrankeiten, being essentially the atlas of skin diseases. In 1844 he discovered and diagnosed a skin disease called "Scabies." After this around twenty-seven thousand of the twenty-two thousand patients he had, had this disease Scabes. A while after that he became able to tell what patients what kind of treatments to use and was able to diagnose what kind of skin diseases they had. This also led up to his discovery of Psoriasis. His sons Hebra and Hans also studied dermatology and followed after their fathers footsteps leading to them both becoming dermatologists. 
How do you get it?
Psoriasis is usually seen as a inherited disorder. Most parents that have it when they're younger usually pass it down to their offspring. Another cause would be that your immune system is mistaking healthy things in your body for bad, unhealthy things or something dangerous. Their are several things that can trigger or cause the psoriasis to appear or reappear: You need to have just the right amount of sunlight, too much or too little can be dangerous, the heat from the sun can cause dry skin. Bacteria from sicknesses or diseases can also trigger the psoriasis. If you consume a lot of alcohol or you smoke anything such as cigarettes it can cause the psoriasis to become more visible; some medications people take can cause the psoriasis and make a reaction and make itself worse and harder to hide.  But one of the main triggers to Psoriasis is actually stress. Most people with psoriasis will tell you that stress causes the skin to become more itchy and the appearance gets worse. A lot get very stressed with their first breakout of psoriasis that it only makes it worse. 
You can find Psoriasis at any part of the skin. You must be careful because you do not treat Psoriasis on different parts of the body the same. Many different parts of the body has different ways of treating the Psoriasis to sooth and eventually eliminate it.
The locations possible for Psoriasis to appear are: Ears, Scalp, Facial, Flexural, Palmoplantar, Mucous Membrane, The Trunk and Limbs, Lower Back, Elbows and Knees, Nails.
The kind of symptoms you get can always vary on the type of Psoriasis you have. But normally you would tend to start seeing flaky skin, or dry and cracked skin, usually on the elbows or knees. The dry cracked skin can be itchy and tend to burn and sting a little bit. When you itch the areas of dry skin, it can break apart and start to bleed. Some people get thickened, pitted, or ridged nails and others can get swollen and stiff joints, which will put quite a strain on people, and that is only going to make the psoriasis get worse because of your stress level.
Usually when the Psoriasis is so severe you would get a prescription from the doctor. When it's light and not as bad you can just use simple creams and oil with vitamins in them and rub it into the Psoriasis. Lots of treatment drugs for Psoriasis can have severe side affects. Most drugs don't work with anyone with Psoriasis, some do and some don't. It is said that when some use lotions and oils on their skin can make it severally painful and stingy. [Maylisa Chung]
Approximately 2.2 percent of the population in the USA have Psoriasis.
That same percentage pertains to the population with Psoriasis worldwide.
Nearly ninety percent of people with Psoriasis state that is was a problem in their everyday life.
Most Psoriasis appears mostly in women and children.
Psoriasis can develop at any age but mostly comes between fifteen and twenty-five.
All together, the cost, of everyone with psoriasis, of medical bills is approximately 11.25 billion annually.
- What is Psoriasis? by Unknown Author, ehealthMD, Accessed Dec.16 2010
- Ferdinand Ritter von Hebra Ferdinand Ritter Von HebraBy Rudolf Kleinert, Who Named it, Accessed Dec.16 2010
- Psoriasis Unknown Author, Goodle Health, Accessed Dec.16 2010
- Psoriasis Triggers American Academy of Dermatology, Psoriasisnet, Accessed Dec.16 2010
- Psoriasis Treatment Mayo Clinic Staff, Mayo Clinic, Nov.4 2009
- Statistics Unknown Author, National Psoriasis Foundation, Accessed Dec. 16 2010