Douglas Hofstadter spent some time interested in letterforms and asking questions like "what variations are still recognizable as an 'A'?" He wrote two essays t

Douglas Hofstadter spent some time interested in letterforms and asking questions like "what variations are still recognizable as an 'A'?" He wrote two essays that ended up in his Metamagical Themas book, Variations on a Theme as the Crux of Creativity and Metafont, Metamathematics, and Metaphysics. Very interesting reading if you are interested in type and lettering. The second one involves the Metafont program that Donald Knuth wrote (in part) to create his Computer Modern font (used in TeX).