This article is from the Apple II Programming FAQ, by Jeff Hurlburt with numerous contributions by others.
A handy utility for quickly viewing Text files under DOS 3.3 or ProDOS
is Copy II Plus.
On the IIgs under the system Finder (the usual "desktop" display
showing drives, folders, etc.) you can, probably, double-click on a
text file to start up an application (program) which will display the
Text and let you make changes.
Note: If you get an error message about not being able to find an
application, you will want to think about setting up a link between
Text type files and some Text editor program such as Teach. Some Text
editor New Desk Accessories (like Shadowrite) will automatically
establish a linkage.
Another way to view and edit Text files is to run a Text editor or
word processor program and load in the file. On 8-bit Apple II's, some
choices include Screenwriter II, AppleWriter, and, depending upon
machine, some versions of Appleworks. On the IIgs you have many
choices including Teach, Shadowrite NDA, CoolWriter, and
Appleworks. --Rubywand
 
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