An I-beam, also known as H-beam (for universal column, UC), w-beam (for "wide flange"), universal beam (UB), rolled steel joist (RSJ), or double-T, is a beam with an I or H-shaped cross-section. The horizontal elements of the I are flanges, and the vertical element is the "web". I-beams are usually made of structural steel and are used in construction and civil engineering.

h4. See Also
* [[construction site]]
* [[steel beam]]

h4. External Links
* "Wikipedia: I-beam":[https://en.wikipedia.org/wiki/I-beam]
i-beam