I-beams are made of single piece of structural steel . It also formed from alloys , aluminium and other material. The most common type of I Beam is steel joist rolled from long piece of billet etc.
The horizontal elements of I Beam i.e I are called as flanges, and the vertical element is called as the web. it generally used in construction and civil engineering.
The purpose of web is to resist the shear force on the other hand function of the flange is to prevent the bending force experienced by the beam.
I Beam has parallel flange which are easier to connect and do not require tapering.
I Beam has deeper web and more suited to carry bending load such as floor beams.
I-beams have different names such as ISMB, ISJB, ISLB, ISWB. ISMB: Indian Standard Medium Weight Beam (ISMB), Indian Standard Junior Beams (ISJB), Indian Standard Light Weight Beams (ISLB), Indian Standard Wide Flange Beams (ISWB).MS-Beam-Chart