A sample from "The Concept of a Metafont", for font rendering comparison purposes

knuth-metafont-sample.tex

%% This recreates the abstract from "The Concept of a Meta-Font" by Don Knuth,
%% https://s3-us-west-2.amazonaws.com/visiblelanguage/pdf/16.1/the-concept-of-a-meta-font.pdf
%%
%% Observe that "modern" Computer Modern as rendered in a PDF viewer(*) is much
%% lighter in weight (has much thinner strokes) than Computer Modern as printed
%% in 1982.
%%
%% (*) In my case, evince 3.30.1 on Ubuntu Linux 18.10 on a 4K screen in 2019.
%% Different PDF viewers on different operating systems and different screens
%% may have different font rendering behavior - in particular, I have heard that
%% Mac OS X's font renderer adds a noticeable amount of weight to fonts at small
%% sizes.

\documentclass[9pt]{extarticle}
\usepackage[papersize={147.5mm,216mm},top=1cm,left=42pt,textwidth=249pt]{geometry}
\usepackage{lmodern}
%\usepackage{variablelm}
\linespread{.88}
\linespread{.8667}
%\linespread{.864}
\usepackage{hyperref}

\begin{document}

\setlength\parindent{0pt}
\setlength\parskip{1em}

\noindent A single drawing of a single letter reveals only a small part of what was in the
designer's mind when that letter was drawn. But when precise instructions are
given about how to make such a drawing, the intelligence of that letter can be
captured in a way that permits us to obtain an infinite variety of related
letters from the same specification. Instead of merely describing a single
letter, such instructions explain how that letter would change its shape if
other parameters of the design were changed. Thus an entire font of letters and
other symbols can be specified so that each character adapts itself to varying
conditions in an appropriate way. Initial experiments with a precise language
for pen motions suggest strongly that the font designer of the future should not
simply design isolated alphabets; the challenge will be to explain exactly how
each design should adapt itself gracefully to a wide range of changes in the
specification. This paper gives examples of a meta-font and explains the
changeable parameters in its design.

Excerpted from \href{https://s3-us-west-2.amazonaws.com/visiblelanguage/pdf/16.1/the-concept-of-a-meta-font.pdf}{\emph{The Concept of a Meta-Font}}, Donald Knuth, in \emph{Visible Language} volume XVI (Winter 1982).

\end{document}