I have a website that will eventually display multiple languages. I notice the common fonts used in web CSS (ex: Arial, Verdana, Times New Roman, Tahoma) and even the newer Vista/Office 2007/VS2008 fonts (Calibri,Cambria, Candara, Corbel, etc) are significantly larger (~350K) than your average (US only?) TTF font (~50k) so these fonts contain most/all the major character sets that common languages (Spanish, French, German, etc) use.
My question is, would somebody confirm that these fonts listed above are acceptable for international use of the major (let's say top 8) spoken languages? If so, then I'm guessing the only purpose of unicode fonts; such "Arial Unicode" (a massive 22mb) is only for dealing with extremely niche dialog, eastern glyphs (Chinese, Japanese) and dead languages?
I'm just looking for some confirmation from developers that have their desktop apps/web apps rendering multiple languages and have a visual confirmation, I'm already in the 99% sure bin but you know what they say about assumption.
Best Answer
I just checked the character set of Calibri and Cambria and confirm that they cover all the major languages of Europe (hence also of America). I can check for the other ClearType fonts if that makes you feel more comfortable, but I doubt the coverage is any different.
As has already been stressed, though, your choice of fonts depends a lot on the exact set of languages you're targetting: usually, you can be confident that any commercial font covers at least all the languages of Western Europe (English, French, German, Italian, Spanish, Portuguese, etc.). If you want to add Polish, Czech, Slovak, etc. to that, you need fonts with “Central European” coverage (usually tagged as CE in the Adobe font library). For Greek, you of course need a font with Greek characters, and for Russian a font with Cyrillic characters (which usually covers Ukrainian, Bulgarian, Serbian, etc. as well). The ClearType fonts support all of the above, btw.
In the end, nothing beats checking it for yourself: if you know what language you want to support, you can examine the font you intend on using, and check for the characters you're looking for. Michael's Everson Alphabets of Europe is a great resource here. It might seem tedious to have to go through all the individual languages, but it's something you really have to do it order to make an informed decision.
If you need to support Arabic or Hebrew, Indic scripts or scripts from South-East Asia, or ideographic scripts, then the picture is wholly different, as has already been said, and I doubt any single font would fit here, except for the very rare fonts that attempt to be comprehensive (which, by the way, is an illusion).