A localization team is rebuilding a 40-language product manual, and every export keeps breaking where the system font runs out of characters. GNU FreeFont, maintained over the years by the GNU FreeFont contributors, was made for exactly that problem. It sits in the sans-serif category, though the family reaches further: the set covers serif and monospace styles too, all built on a Unicode base, with support for 612+ Latin-based languages. Twelve files ship in the family, so you have multiple weights and styles to work with instead of one lonely cut, and the main file here is the regular.

That range makes it a sensible default for multilingual software documentation, open source README files and inline code samples, academic papers loaded with diacritics, and nonprofit or government forms that need to render the same way on any machine. Letterforms are plain and unfussy, which is what you want when the content is doing the talking and the reader is scanning for information rather than admiring the type. Mixing the sans for body copy with the monospace for terminal output in one document keeps things consistent, since both come from the same family.

One practical note: this family was drawn for coverage rather than for headline polish, so at large display sizes check the spacing on your specific string and tighten tracking by hand if letters sit loose. At text sizes it behaves well left alone, though extra line height helps pages loaded with accents. Open license, commercial use allowed, files hosted here for direct download below.