Sd - A Square Dance Caller's Helper

                  1B>
            2G>   4B<   1G<
            3G>   2B>   4G<
                  3B<

      [boys trade] and circle 1/2

                  3G>
            2B>   3B<   2G<
            4G>   1B>   4B<
                  1G<

Sd: a checker-moving program that is powerful, sophisticated, accurate, and reliable.

The current version of Sd/Sdtty is 39.76, released on Aug 30, 2025.

This reflects recent changes in the C3 list.

There is a new experimental call: "<ATC> down the line", as in "flip down the line"
or "chase down the line". Do the tagging call to the 3/4 tag position, then the centers turn thru
while the ends turn around and courtesy turn those centers. This call has been set to C3X.

Downloading and installing may be difficult because of virus-checking software.
You may need to disable some of that software when downloading and installing.
See the download page for details. All versions of Sd and Sdtty are scanned before release,
and the computer on which Sd is developed is scanned frequently.

There is a "Frequently Asked Questions" (FAQ) file. See the link below.

Sd and Sdtty are distributed under the GNU General Public License. Source files are available below.

Hints for inexperienced users:

(1) You may find that Sd is more user-friendly than Sdtty, particularly if you are having trouble with sessions or abridgement files. It will show you the startup options more clearly. You can type commands at Sd the same way you type at Sdtty. It just looks different.

(2) If in doubt about how to enter some complex call, type part of the call and a question mark. For example, if you want to know how to modify the star turn on a chain reaction, type "chain reac?". Then, following its hint, type "tion, turn the star 1/2".

(3) You may have heard that Sd lets you type complex calls directly, using brackets, as in "catch [motivate] 3". This is true, but you may find it unwieldy if you are accustomed to entering things piecemeal. You can still do it that way. Remember to type "<anything>", not just "<any>". For example, type "catch <anything> 3". (Not sure about that? Type "catch" and a question mark.) Then type the "motivate".
 

Frequently Asked Questions

 

Show off!

A sample of fun things Sd can do. These have all been featured on this page at one time or another.
 

Background

Background and availability info.
 

Get Sd now!

Be running the latest, fully-functional version on your Windows PC in minutes.
Or download the program, in source form, for most varieties of Unix You will have to compile it yourself.
You should be able to compile a version for a Mac by downloading the sources and typing "make" in a terminal window.
 

Documentation

Browse or download documents about Sd, including the release notes and the users manual.
 

Source Code

This is the source code for Sd and Sdtty. It is distributed under the GNU General Public License.
 

Want to report a bug or ask a question?  Email <wba@alum.mit.edu>.