GNU FreeFont is apparently based on the URW fonts, but metric compatibility was not retained. The Times equivalent is FreeSerif. ( fonts-freefont-ttf) GUST TeX Gyre is based on the URW fonts. The Times equivalent is TeX Gyre Termes. ( fonts-texgyre) URW released open-source clones of the 35 Postscript fonts for ghostscript. The Times equivalent is Nimbus Roman. The metrics are slightly different from Times New Roman. Google commissioned the Croscore fonts, designed to be metrically compatible with Microsoft fonts. They appear to be slight modifications of the Liberation fonts. The Times New Roman equivalent is Tinos. ( fonts-croscore) Red Hat commissioned a set of fonts designed to be metrically compatible with Microsoft fonts. The equivalent of Times New Roman is Liberation Serif. They have a significantly different look and feel from the original fonts. ( fonts-liberation2) Since Adobe chose Linotype's Times for use in its products, Monotype was forced to modify the original design to fit Times metrics. There was also a bitmap version 'Tms Rmn', which was later renamed 'MS Serif'. Microsoft has included Times New Roman with its operating systems. The PostScript language defines 35 core fonts in PostScript 2. Among them is the serif font family Times. Times was Linotype's copy of Monotype's Times New Roman, which was commissioned for The Times in 1931. A properly configured system should automatically substitute one of the following fonts, if available. Hence, to find something similar, you want to look at other serif fonts. It follows from the above descriptions that Times New Roman is a serif font. Examples of sans-serif fonts include many fonts normally used for headlines, fonts used for computer screen menus, and so on. This is commonly used when the font size is small relative to the medium's resolution or dot pitch, because the extra ornamentation at the end of the glyph lines would obscure the shape of the glyph itself. The ends of the glyph lines are straight and terminate abruptly. 'sans serif' fonts lack serifs (that's where the 'sans' comes from it's French for 'without').

Serif fonts are typically used in print for large blocks of text, as they are generally considered easier to read when the resolution is high enough to properly render the serif.

That's the little ornament or line at the end of the glyph lines. I don't know which exact font of those that come by default with Ubuntu 12.10 would be the closest visually to Times New Roman (though Liberation Serif seems a good fit), but: What is the closest alternative font of Times New Roman in Ubuntu 12.10? Is it serif or sans serif or something else ?

Find free alternative fonts