Just FYI and amusement. http://theweek.com/articles/617776/how-identify-language-glance "How to identify any language at a glance"
Topic on Talk:TextCat
Cool! This is actually a much lower resolution version of the ideas behind TextCat. Certain letters, combinations of letters, and the relative frequencies of the letters or combinations is how TextCat identifies languages. It's made more complicated by the length of the text we're dealing with; queries are often very short, and not all of the distinguishing features of a language will not be present in a short query string.