An
-beam, also known as
H-beam,
W-beam (for "wide flange"),
Universal Beam (UB),
Rolled Steel Joist (RSJ), or
double-T (especially in
Polish,
Bulgarian,
Spanish,
Italian and
German), is a
beam with an or H-shaped
cross-section. The horizontal elements of the "" are known as
flanges, while the vertical element is termed the "web". I-beams are usually made of
structural steel and are used in construction and civil engineering.