$language = $_SERVER['HTTP_ACCEPT_LANGUAGE'];
Yes, the value of
$_SERVER['HTTP_ACCEPT_LANGUAGE'] is a string -- see
Its content is sent by the browser -- which explains why you get different results depending on the browser you are using : most likely, your Firefox is configured to request pages in english (high priority) or japanese (low priority), while your IE is configured to request pages in chinese.
This is because that HTTP header can contain :
The idea being that the server should respond, using the language that suits "the best" what's requested by the user.
About parsing that header, this blog-post might be a interesting read : Parse Accept-Language to detect a user's language
There is a portion of code proposed to parse that HTTP header -- and it generates an array that looks like this (quoting) :
Array ( [en-ca] => 1 [en] => 0.8 [en-us] => 0.6 [de-de] => 0.4 [de] => 0.2 )
Which is an array of languages, sorted by priority, in descending order -- which is probably what you want.