What were the significance of El Alamein campaign?

Answer 1

It stopped the German forces in Africa led by Rommel and was the turning point in the African campaign. Ultimately the Germans were pushed across Africa and had to give up the campaign. Later it paved the way for the attack on Sicily and Italy, and subsequently Normandy.

Answer 2

It was the first defeat for Germany. It kept Germany from taking the Nile, and then the Middle East oil fields.