utf8 option for the LaTeX distribution
inputenc package. The separate package ucs
provides wider, but less robust, coverage via an inputenc
option utf8x. Broadly, the difference is that
utf8 deals with “standard LaTeX fonts” (those for
which LaTeX has a defined encoding), while utf8x deals
with pretty much anything for which it knows a mapping of a Unicode
range to a font. As a general rule, you should never use
ucs/utf8x until you have convinced yourself that
inputenc/utf8 can not do the job for you.
‘Modern’ TeX-alike applications, XeTeX and
LuaTeX read their input using UTF-8
representations of Unicode as standard. They also use TrueType or
OpenType fonts for output; each such font has tables that tell the
application which part(s) of the Unicode space it covers; the tables
enable the engines to decide which font to use for which character
(assuming there is any choice at all).
This answer last edited: 2011-03-07
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