Hi scorp,
Allaah and YHWY are the same God.
I'll give you a brief history as I know it.
The Torah is the Ten commendents and the set of laws given to Moses. When the hebrew text of the first five books were analyzed, it was found out that the fifth book possess a completely different language style, the language style of this Book (Deuat.) is identical to Kings, Joshua, and Judges. Which indicate different authors for these books. Howveer the OT was written in the captivity of Babylon. Some of the prophets sayings were earlier recorded as well as the first five books, the rest was written during during captivity. However only the first five books were used after the return, but when the Torah was banned Jews were forced to refer to the other books they had. After the ban, they were all included and took their final form as we know today.
about the NT i think I already talked about it on so many occasions.
Hope this helps.
Later.