The old arabic language of the Qu'ran?

The muslim holy book quran is said to be written by Allah, and transferred to Muhammed, who wrote down the earthly version. Though, this was a very long time ago, and the arabic language then was probably very different than the modern arabic. It is also said by muslims that the quran should not be translated, as the inner meaning of the quran should get lost. It it therefore "tranlated" into book called something like "The meaning of the qu'ran". Now i wonder, are there a new-arabic version of the quran, or do the arabc understand the ancient arabic language? Maybe the language havn't change? Or?