We survey the literature on fractional calculus and fractional differential equations with emphasis in the context of causal distributions, which has been an area of rapid development in recent years. We examine the main concepts neccesary for the study of fractional formalism, highlighting functions expandable into fractional power series and the asymptotics results of fundamental solutions developed by Matignon. We give some new applications of this area on the asymptotic behaviour of a system modelling rigid structures floating in a viscous fluid