ook
ookThis 
ook
ook is intended to help beginning users of the NRAO 
stronomical 
mage 
rocessing 
ystem (


)
by providing a recipe approach to the most basic 


 operations. While it illustrates some aspects of



, it does not pretend to be complete. However, it does include detailed instructions for running
many important items of 


 software. With these as a model, the user should be able to run other



 software aided by the EXPLAIN, HELP and INPUTS files and the complete index of software given in
Chapter 13 of the 
ook
ook. In this edition, some of the chapters have matured into something more
like a users’ manual, than a beginners’ cookbook. These sections provide an overview of a few less
basic, but nonetheless interesting, programs which often seem to be forgotten even by experienced



 users. To assist the beginning and infrequent user, appendices have been added to provide outlines of
continuum, spectral-line, and high-frequency calibration procedures, primarily geared to users of the VLA,
and a simplified outline of VLBA data reduction. A guide to reduction of data from the historic VLA
appears in Appendix O. To assist in finding information in this now large document, an index has been
added.



 software is changing and growing continually. This edition of the 
ook
ook describes the 31DEC24 (aka
“


 for the Ages (Aged), version 25”) release of 


. Some chapters have information only
from earlier releases. When something only applies to fairly recent versions of 


, a comment to
that effect is made. Features remain in later releases even if the particular comment does not say as
much. There were many changes in 


 software between the seventh (15JAN94) and the sixth
(15JUL90) edition of the 
ook
ook. The chapter on the 


 calibration package for continuum,
spectral-line, solar and VLBI data (Chapter 4) was revised in 2018 to describe calibration and editing of the
Expanded VLA. Material applying to the old VLA was moved to Appendix O (old). The list of current



 tasks (Chapter 13) has been updated and reflects the extensive improvement and expansion of



 software. The chapters on imaging and improving images were merged as were the chapters on
interactive and hard-copy displays. These mergers reflect in part the mergers of these operations. The
chapter on spectral-line imaging (Chapter 8) has been revised with the assistance of Elias Brinks. Phil
Diamond, John Conway, Athol Kemball, and Ketan Desai have rewritten the chapter on VLBI calibration
and imaging (Chapter 9). Appendix Z contains instructions and advice peculiar to the individual



 sites of the NRAO. This has been revised extensively to reflect the migration of much of the data
reduction at NRAO sites away from VAXes and Convex computers to Sun and Linux workstations. The
ninth edition has an Index which is current and updates concerning editing, calibration, imaging
and single-dish processing in the 15APR98 and later versions of 


. This edition still contains,
essentially unchanged, the helpful glossary of astronomical and computing terms written by Fred
Schwab.
Paper copies of recent editions of the 
ook
ook are no longer available from NRAO. However, much of the



 documentation, including the 
ook
ook, is now available on the “World-Wide Web” so that it may be
examined and retrieved over the Internet (start with “URL” https://www.aips.nrao.edu). This edition of
the 
ook
ook is issued in a ring-binder format with a chapter-based page numbering system. This
allows us to update individual chapters without altering the pagination of others and to make each
chapter available individually over the Internet. The documentation is also included with every copy of



 shipped.
Additional written documentation on 


 is available in several forms. A programmers’ reference manual
                                                                                         
                                                                                         
called Going AIPS is available in two volumes. This was revised completely for the 15APR90 release due to the
upgrading of the 


 code to FORTRAN-77 and to reflect the extensive additions and improvements to the
software. Unfortunately, it has not been revised since but it continues to be quite useful. The first volume is
intended for applications programmers, while the second volume is needed by programmers developing



 for new peripheral devices or computers. Going AIPS may be obtained from the 


 web
site.



 provides run-time documentation in the form of HELP and EXPLAIN files which may be viewed at the
terminal or printed. (See §3.8 for explicit instructions.) Should these not suffice, consult your local 


 Manager
and then, if needed, e-mail the 


 programmer at daip@nrao.edu. Although individual 


 programs have
often been written, and are best understood, by a single programmer, the 


 group as a whole assumes
responsibility for all released software. Anyone in the group will attempt to help you or, at least, to identify another
member of the group better able to help you.
Finally, users are encouraged to recommend new and better analysis and display tools and to help debug the existing software by entering “Gripes” (see §11.1). Please note that examples of bugs that are documented by printouts of inputs, message logs, etc. are most useful to the programmers. Also note that written bug reports are much more effective than verbal reports. E-mail to daip@nrao.edu reaches everyone in the group.