I-Beams differ from wide flange sections (which are much more common in framed construction), in that metal I-Beams are formed via rolling or extrusion, whereas wide flange sections are formed by welding metal plates together. As a result, I-Beams typically have tapered flanges.
In modern construction, I-Beams are typically reserved for the guide rail in an elevator shaft. Wide flange sections are the common metal beams/columns seen by most people.
