Hochschild cohomology : some methods for computations 1

We present some results on computing Hochschild cohomology groups. We describe the lower cohomology groups and provide several examples. In the particular case of hereditary algebras, radical square zero algebras and incidence algebras, we construct convenient projective resolutions that allow us to compute their cohomology groups. Finally, we show an inductive method to compute the Hochschild cohomology groups.