Nimbus Roman No. 9 L

Nimbus Roman is a serif typeface created by URW Studio in 1982. Nimbus Roman No. 9 L is a serif typeface created by URW Studio in 1987, and eventually released under the GPL and AFPL (as Type 1 font for Ghostscript) in 1996 and LPPL in 2009. It features Normal, Bold, Italic, and Bold Italic weights, and is one of several freely licensed fonts offered by URW++. Although the characters are not exactly the same, Nimbus Roman No. 9 L has metrics almost identical to Times New Roman and Times Roman. It is one of the Ghostscript fonts, a free alternative to 35 basic PostScript fonts (which include Times). It is a standard typeface in many Linux distributions.

From the Wikipedia article “Nimbus Roman No. 9 L”, licensed under CC BY-SA 4.0.

Serif typefaces like this are the traditional choice for book body text: the serifs guide the eye along the line in long passages. Set novels at 10.5–12 pt with 125–140% leading.

Commercial typefaces require a licence that covers embedding in PDFs and ebooks; check the foundry's licence before you publish.