The following listing is of the example TeX file story.tex, which should be available in the .../texmf/tex/plain/base/ part of your TeX distribution. It is also listed on page 24 of D E Knuth’s The TeXbook. A copy is included in the TeX2page distribution.

You can of course use any example file you want. story.tex merely happens to be the “first” example file in the TeX collective consciousness. 74.3% of all TeX users learned TeX by analyzing this file.

\hrule
\vskip 1in
\centerline{\bf A SHORT STORY}
\vskip 6pt
\centerline{\sl    by A. U. Thor} % !`?`?! (modified)
\vskip .5cm
Once upon a time, in a distant
  galaxy called \"O\"o\c c,
there lived a computer
named R.~J. Drofnats.

Mr.~Drofnats---or ``R. J.,'' as
he preferred to be called---% error has been fixed!
was happiest when he was at work
typesetting beautiful documents.
\vskip 1in
\hrule
\vfill\eject