Inflammation is a process that often occurs in order to fight off foreign invaders in the body including viruses, bacteria, and fungi. In response to such organisms, the body's immune system begins to produce a variety of cells and chemicals intended to stop the invasion. In the case of Ulcerative colitis cells from the immune system are collected in the bowel wall, this leads to inflammation, injuring of the bowel. This injury causes tissues of the affected part of the body, normally the colon and rectum to become swollen, red, warm, and painful especially its mucous membranes. The inflamed membranes develop patches of tiny ulcers, causing diarrhea that contains blood and mucus. Inflammation usually begins in the rectum and lower intestine and spreads upward to the entire colon.Ulcerative colitis is largely a disease of nonsmokers and patients who have quit smoking. This illness is usually chronic, with repeated flare-ups and remissions. This means there are times when a person feel well and times when he/she feel ill. Half of the people who have ulcerative colitis have only mild symptoms. A rapidly progressive initial attack results in serious complications in about 10% of people.Ulcerative colitis is a disease that causes inflammation and sores, called ulcers. This happens in the lining of the rectum and colon. Ulcers form where inflammation has killed the cells that usually line the colon, then bleed and produce pus. Ulcerative colitis is usually continuous from the rectum onwards, with the rectum almost universally being involved. There is rarely peri-anal disease, but cases have been reported. This ulcer causes diarrhea, bleeding, and mucus. With time the patient may become anemic, protein and salt depleted.Ulcerative colitis is generally found in younger people before they reach age 30. But the disease can occur in people in their 60s and later in life. About 80% are between the ages of 20 and 40 years in the UK. Approximately 600,000 people in the United States are affected. Ulcerative colitis is statistically 20% hereditary. It is more common in people of Jewish descent. Rarely seen in Eastern Europe, Asia, and South America, and is rare in the black population. For unknown reasons, an increased frequency of this condition has been recently observed in developing nations.