  I review evidence that galaxies form from gas that falls into potential wells
cold, rather than from virialized gas, and that formation stops once an
atmosphere of trapped virialized gas has accumulated. Disk galaxies do not have
such atmospheres, so their formation is ongoing. During galaxy formation
feedback is an efficient process, and the nuclear regions of disk galaxies blow
winds. The cold infalling gas that drives continued star formation has a
significant component of angular momentum perpendicular to that of the disk.
Extraplanar gas has to be understood in the context set by nuclear outflows and
cold skew-rotating cosmic infall.
