Swift image files are all stored in FITS format
and should be readable with most FITS readers or displayed with
most FITS viewers (such as DS9 or Fv). The images are
typically in image extensions with most files
containing multiple extensions representing different
observations or filters.
The recommended way to read and analyze Swift data
is using the Swift software distributed by HEASARC as part
software package, or available online using the
Hera data analysis service.
UVOT Software Guide
for more information on the available UVOT software
tools from HEASARC.