Mount Horeb, although there is some variance of opinion as to whether Mount Horeb is entirely synonymous with Mount Sinai or just a lower peak on the way up.

In certain biblical passages these events are described as having transpired at Horeb, but though there is a small body of opinion that Sinai and Horeb were different locations,[2]they are generally considered to have been different names for the same place.

According to the researchers of the Documentary hypothesis, the name Sinai is only used in the Torah by the Jahwist and Priestly Source, whereas Horeb is only used by the Elohist and Deuteronomist.[11]

See link 'Biblical Mount Sinai

According to the documentary hypothesis, one of the sources for the first five books of The Bible (the 'Pentateuch') is named the "Elohist source", because he referred to God as El or as Elohim.. Rather than the Ten Commandments provided by the Jahwist source, the Elohist text contains a "law code" (at Exodus 21:2 - 23:33), which is believed to have been an originally separate document, known as the "Covenant Code".

Exodus 21 is part of that law code, a set of cammandments for the people of Israel. The most famous commandment in Exodus 21 is at verses 22-23, which say that men who cause a woman to miscarry are guilty of a civil offence, at the discretion of her husband.

For more information, please visit:

http://christianity.answers.com/bible/the-pentateuch-explained
http://christianity.answers.com/bible/the-book-of-exodus