  Strong absorption lines are common in rest-frame UV spectra of AGNs due to a
variety of resonant transitions, for example the HI Lyman series lines (most
notably Ly-alpha 1216) and high-ionization doublets like CIV 1549,1551. The
lines are called ``intrinsic'' if the absorbing gas is physically related to
the AGN, e.g. if the absorber resides broadly within the radius of the AGN's
surrounding ``host'' galaxy. Intrinsic absorption lines are thus valuable
probes of the kinematics, physical conditions and elemental abundances in the
gas near AGNs. Studies of intrinsic absorbers have historically emphasized the
broad absorption lines (BALs) in quasars. Today we recognize a wider variety of
intrinsic lines in a wider range of objects. For example, we now know that
Seyfert 1 galaxies (the less luminous cousins of quasars) have intrinsic
absorption. We also realize that intrinsic lines can form in a range of AGN
environments --- from the dynamic inner regions like the BALs, to the more
quiescent outer host galaxies >10 kpc away. This article provides a brief
introduction to current observational and theoretical work on intrinsic AGN
absorbers.
