N-3 polyunsaturated long chain fatty acids and especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are known to limit inflammation and to improve its resolution. The benefits resulting from the use of EPA and DHA are numerous, they are used for treating asthma and arthritis, for controlling blood pressure and vascular reactivity and have been shown to have antitumor effect. While the effects of these polyunsaturated fatty acids on improving the resolution of inflammation are well evidenced, the mechanisms involved in this process remained unclear until the discovery of protectins and resolvins. The goal of this paper is to give an overview on the biosynthesis, the metabolism and the biochemical and physiological functions of these molecules derived from EPA and DHA.