On H^1 of finite dimensional algebras Claude Cibils A para\^itre dans Proceedings "Homologie et th\'eorie des repr\'esentations" Vaquer\'\ias, C\'ordoba, Argentina, 1998. Pr\'epublication 1999-03, Universit\'e de Montpellier 2, France We review results on the first Hochschild cohomology vector space of a finite dimensional algebra, in particular for path algebras modulo a ``pre-generated'' ideal. In case of a monomial algebra which quiver has no oriented cycles, a dimension formula is provided. The general monomial case will be considered in a paper in progress with M. Saorin.