Generally speaking, file formats don't have much of an impact on day-to-day computing. Most file types can work independently of operating systems or software. Exceptions exist:software for one operating system will not work on another, and fonts for Mac OS X tend to be in the .dfont file format.
SummaryFont File FormatsTrue TypeOpen TypeConclusionBoth problems can be solved in different ways; we have already covered .dfont file formats and WINE is a renowned solution for running Windows software on UNIX systems.
Most people have favorite file formats for niches; some favor MP3, others FLAC, others AAC, etc. Have you ever looked at your font library the same way?
While fonts are something people expect to "just work with", their formats do matter. We've already mentioned the .dfont format used in OS X as an example, but Macs can use the two major font formats you'll see popping up again and again:OpenType (.otf) and TrueType (.ttf).
At one time, the benefits of TrueType were innumerable. This allowed greater control over how a font appeared on screen with hints, and anti-aliasing helped create an attractive font even without modern screen resolutions.
Developed in 1996, OpenType is newer than the TrueType format. Both fonts therefore have similar levels of support on different operating systems. Generally speaking, you can identify an OpenType font by its .otf file format… but not always. As this fairly advanced article outlines, it is possible to have an OpenType font with a .ttf file format.
OpenType supports more features, such as "fi" ligatures automatically replacing individual letters typed together. Some of these features are only really interesting with software like Adobe Illustrator; Monotype Font Store suggests that you use TrueType over OpenType if you tend to rely on Microsoft Office software.
By now, you should have a better understanding of the two most common font formats, and you'll probably have come to your own conclusion as to which format you prefer.
We don't recommend getting too obsessed with file formats; for everyday writing, fonts shouldn't be too much of a problem for you. If you're working on projects and typesetting, you'll probably need a better understanding of fonts and their characteristics.
Not sure if a font you downloaded is right for your project? We've got you covered – we've looked at a variety of software licenses, including SIL Open, which is written specifically for fonts.
