  A review is given on the various aspects of gamma-ray burst afterglow
observations, and the inferences derived from the data. After a short history
of optical transient search and the BeppoSAX discoveries, the main topics
included are prompt multiwavelength emission, dark bursts, spectral lines line
and continuum variability, the early light curve behaviour, jet breaks, X-ray
flares, late afterglow features, polarization, and orphan afterglows.
