What is center pivot irrigation ?and does it conserve water,?

"The water is supplied to the center of the field in pivot systems. The irrigation line is the length of the radius of the circle, and goes around the field, pivoting at the center." -- a href="http://www.wtamu.edu/~crobinson/Irrigation/pivinfo.html" rel="nofollow"http://www.wtamu.edu/~crobinson/Irrigati…/a