HUH?
What the HECK?
what in the world?
short form of "What the fuck?"
commonly used when trying to understand something incomprehensable
Ikurama Masato the foreign exchange student from japan read the newb's post in the forum / chat room and proclaimed "da fuck isu hi tarukin abaato? yuusu riaru engirishu idiato!" and promptly began typing his insulting reply.