Variable according to filter language

Hello:
I’m using the Plugin and would need to know:
(When the language is changed (in the front-end)) There is a variable that stores the language is in each case? Would need this to print specifications (like ‘en-EN’ or ‘es-ES’) in some HTML Tags, according to the language being displayed (eg in tags from ‘header.php’). Or if I wanted to show specific content only in the ‘X page English’ and not show it on the same page but in Spanish, filtering with this variable.
thanks

http://ww.wp.xz.cn/plugins/multilingual-press/