Seyfert galaxies and quasars were first discovered through optical and radio
techniques, but in recent years high-energy emission, that can penetrate
central gas and dust, has become essentially the defining characteristic of an
AGN. AGNs with extended radio jets are of particular interest, since the jets
signal source orientation. However, the jets extend into the cores, where they
are faster and more compact. Special-relativistic effects then cause jet
brightness and variability time-scales across the electromagnetic spectrum to
be strong functions of jet orientation. Jet X-ray emission is confused, to
varying degrees, with that from the central engine, but can be measured, at
least in a statistical sense, through considerations of the multiwaveband
spectrum and the level of intrinsic absorption. The rich high-energy structures
found in jets which are resolved with Chandra inform our interpretation of the
inner structures. In particular, it is found that shocks are prevalent and
don't necessarily disrupt jets, and that one-zone models of emission near
shocks are an over-simplification.Comment: Review to be published in Proceedings of the workshop "Multiband
Approach to AGN", held on Sep.30-Oct.2 in Bonn. Publication: Memorie della
Societa Astronomica Italiana, v. 26, No.1 (2005). 8 page
