All the BASIC programs that have appeared in S&T since 1984 are collected on our Web site at SkyandTelescope.com/resources/software. All you need to run them is a BASIC interpreter or compiler. Interpreters let you edit and execute the BASIC listings; compilers can also turn them into standalone applications.

Back in the 20th century, Microsoft Windows included a BASIC interpreter. You can still obtain the program, called QBasic, by downloading a file called OLDDOS from Microsoft (http://download.microsoft.com/download/win95upg/tool_s/1.0/w95/en-us/olddos.exe). Unpack its contents into an empty folder, and you’ll have QBasic and its help file. (You’re supposed to have a valid licensed copy of MS-DOS or Windows 95/98 to have the right to install QBasic, per Microsoft’s Use of Software statement.)

You don’t have to use QBasic, however. Other interpreters and compilers exist — some for free — for various operating systems. To explore the options, see http://basic.mindteq.com and www.nicholson.com/rhn/basic/#2.

— Stuart J. Goldman