H beam is a structural beam made of rolled steel. It is incredibly strong. It gets its name because it looks like a capital H over the cross-section. H-beam has wider flanges than I-beam, but I-beam has tapered edges. The width is the flange and the height is the web. The difference between the H and I beams is the flange per band ratio. The H beam tends to be heavier than the I beam, which is why some say it is better than the I beam, but this is subjective, as the H beam is generally heavier.