Bernstein-Gelfand-Gelfand showed that the derived category of coherent sheaves on the projective n-space Db(cohPn) is equivalent to the stable ategory of the category of Z-graded finite-dimensional modules over the exterior algebra. At the same time Beilinson gave a description of Db(cohPn) which can be interpreted in terms of tilting theory. We compare these two characterizations using Happel's description of the derived category of modules over a finite-dimensional algebra of fnite global dimension.