Hi, By default, groff uses Times Roman, as I'd expect.
$ groff <<<'hello world!' | grep Times %%DocumentNeededResources: font Times-Roman %%IncludeResource: font Times-Roman /Times-Roman@0 ENC0/Times-Roman RE /F0 10/Times-Roman@0 SF(hello w)72 12 Q(orld!)-.1 E 0 Cg EP $ But on most of our systems, that font's unavailable and another is used in its place. $ fc-match Times-Roman n021003l.pfb: "Nimbus Roman No9 L" "Regular" $ https://en.wikipedia.org/wiki/Nimbus_Roman_No._9_L says Although the characters are not exactly the same, Nimbus Roman No. 9 L has metrics almost identical to Times The "almost" niggles. :-) Running GhostScript's ps2pdf(1) embeds the Nimbus substitute, so even those with Times won't see it. (Unless the embedded font is a fallback; I haven't examined the PDF enough to see; `qpdf -qdf'.) Should I be telling groff that I want to use those Nimbus fonts so it uses their metrics rather than the "almost identical" Times' ones? Cheers, Ralph.