The dumb interface was mainly intended for those who wanted to play
Interactive Fiction, but had just a C compiler and that's it.  You get
no screen control; everything is just printed to the terminal line by
line.  The terminal handles all the scrolling.  While this can be an
annoying way to play IF, it might be the best you can do for a
particular machine, especially when the curses library is inadequate and
installing ncurses isn't an option.  It's also good for getting Frotz to
run when you have a C compiler and know nothing else of how to do
things.  This way you can run Frotz on VMS, MVS, VM/CMS and all those
other stodgy operating system.  More on that later.  Maybe you'd like to
experience what it's like to play Adventure on a teletype.

A much cooler use for compiling Frotz with the dumb interface is that it
can be wrapped in CGI scripting, PHP, and the like to allow people to
play games on webpages.  It can also be made into a chat bot.

Games that move the write little windows of text over the main body of
text are hard to read because with the dumb interface, Frotz doesn't
know how to produce inverse text.  Games that make use of timed-input
can be played, but you must manually increment the timer (see the dfrotz
manpage).  Games that move the cursor around a lot are probably
unplayable.  These include games like Andrew Plotkin's "Freefall" and
Torbjorn Andersson's "Robots".

The dumb interface code was created by Alembic Petrofsky
<alembic@petrofsky.berkeley.ca.us> in 1997 for Frotz 2.32.