I am running Windows XP. Although notepad, Office etc show boxes, proper text is displayed in Firefox. If the system doesn't have the font for a language, how can the web browser manage to circumvent and display the script? How is this done? I am new to Unicode and this is really baffling to me.
When a browser is displaying text in a font specified by the HTML or by the browser, it may come across characters which are not present in that font.
This is particularly the case where the encoding of the web-page is UTF-8, for example, as no single font includes the million or so characters defined by Unicode.
In previous decades, browsers used to display a stand-in character such as an empty square or diamond instead of that character.
For some time now, most browsers, when they need to display a character not in the current font, will now effectively search through all the fonts installed in the computer until they find a font that contains the character needed. This means that browsers are much less likely to display characters as empty squares.
More recent versions of Microsoft applications such as Notepad now do something similar. These applications now use system libraries that do this searching for characters which are unavailable in the current font.