Couscous is a tiny little pasta made of wheat or barley. In North America, wheat couscous is widely available and is generally quick-cooking.
To make fluffy couscous every time is all in the ratio of water to couscous. The general rule is 1 1/2 cup of water for every 1 cup of couscous. One cup of dry couscous will turn into 4 servings after you cook it.