I will discuss the scaling properties of Barkhausen noise, produced by macroscopic domains reversal when a disordered magnet is driven by an eternal field. Distribution of size and duration of Barkhausen pulses and shape of the pulses give information on the microscopic details of the magnetization process, and are used as a quantitative comparison between theoretical models, simulations and experiments. After discussing how to examine the average pulse shape for some simple stochastic processes, I will analyze scaling properties and average pulse shape for a model which succesfully describes a class of materials and compare the results with experimental measures.