Nowadays the spintronic related phenomena are widely investigated since very promising device concepts have been proposed. Combined experimental and theoretical studies enabled a tremendous evolution of this topic in the case of confined magnetic systems such as thin films, nanopillars or nanowires. The magnetization dynamics inside these magnetic nano-objects must be precisely understood and controlled for ensuring their efficient operation. The view point from micromagnetic modelling will be presented starting with the numerical tools and their use to carry extended numerical studies. Several types of spintronic devices will be addressed combining analytical and numerical modelling intimately related with experimental results.