What is the difference in between a hemorrhoid and a polyp?

Vein vs gut lining: Both hemorrhiods and polyps are abnomalities associated with the colon. The hemorrhoid is a vein that has swelled and cause pain & itching. The polyp is an abnormal growth of the lining of the colon. It is usually painless and diagnosed incidentally on colonoscopy. Polyps can degenerate into cancer and need to be removed. Hemorroids are a nuisance and removed for reasons of bleeding or discomfort.

Big difference: A hemorrhoid is found only in the anal canal and is related to the veins of the anal canal. They are benign, although they can bleed and be painful. A polyp is a growth in the gastrointestinal tract. While they tend to grow in the colon, they can be found anywhere in the GI tract. They can get quite large. Some of them have the potential to become cancer. Colon polyps should generally be removed.

Different cell type: Colon polyps are benign or malignant growths of the cells of the inner lining of your GI tract (~20 feet long!), while hemorrhoids are located just in the last 2 inches of your rectum (your anus and anal canal). All polyps should be removed due to cancer potential, while you can live with hemorrhoids (although you may not want to :).