title: What is the point of STL Character Traits?
body: <p>I notice that in my copy of the SGI STL reference, there is a page about Character Traits but I can't see how these are used? Do they replace the string.h functions? They don't seem to be used by <code>std::string</code>, e.g. the <code>length()</code> method on <code>std::string</code> doesn't make use of the Character Traits <code>length()</code> method. Why do Character Traits exist and are they ever used in practice?</p>