The cosmic infrared background records much of the radiant energy released by
processes of structure formation that have occurred since the decoupling of
matter and radiation following the Big Bang. In the past few years, data from
the Cosmic Background Explorer mission provided the first measurements of this
background, with additional constraints coming from studies of the attenuation
of TeV gamma-rays. At the same time there has been rapid progress in resolving
a significant fraction of this background with the deep galaxy counts at
infrared wavelengths from the Infrared Space Observatory instruments and at
submillimeter wavelengths from the Submillimeter Common User Bolometer Array
instrument. This article reviews the measurements of the infrared background
and sources contributing to it, and discusses the implications for past and
present cosmic processes.Comment: 61 pages, incl. 9 figures, to be published in Annual Reviews of
Astronomy and Astrophysics, 2001, Vol. 3