Hemorrhoid or haemorrhoid (also commonly called piles) are vascular structures (similar to veins) in the anal canal which help with stool evacuation. We only speak of hemorrhoids (or piles) when they become swollen or inflamed. But Hemorrhoids are a normal part of the anatomy and everyone has these structures. They act as a cushion that is made of complex tissue. Their job is to aid the passage of stool. Hemorrhoids are very common. Nearly three out of four adults will have hemorrhoids from time to time.