What type of region was the Fertile Crescent and why?

The Fertile Crescent is an area of good farmland in the Middle East from which it is commonly believed civilization began. The name "Fertile Crescent" was coined by an archaeologist James Breasted in one of his textbooks, in which he states

"There is no name, either geographical or political, which includes all of this great semicircle ... Hence we are obliged to coin a term and call it the Fertile Crescent."

If you had to say what type of region the Fertile Crescent is ... I'd just give them the definition.