He nature of Descartes program of radical doubt in the first two meditations of his Meditations on First Philosophy

What is the nature of Descartes program of radical doubt in the first two meditations of his Meditations on First Philosophy. Make sure that you include discussions of the following points along the way: the reason that Descartes engages in his program of radical doubt, what the dream hypothesis and the evil deceiver hypothesis are supposed to cast doubt upon, and the Cogito.