Two horizontal planes, known as flanges which are connected by one vertical component, make up an I-beam, as the shape of the connection creates an uppercase “I” in the cross section. The upper and lower flanges of an I beam have a slope, making the flanges thin outside and thick inside.

The I-beam is the most commonly used beam in structural steel builds. The design and makeup contribute equally to making an I-beam capable of handling a variety of heavy loads. Because of the impressive load bearing capabilities, I-beams are widely used in construction.