A simple efficient approach describing the interaction of various quantum targets with short electromagnetic (EM) pulses firstly proposed in [1] is reviewed. This approach is based on the expression for the photoprocess probability in terms of the cross section and the Fourier transform of the EM pulse. Our method makes it possible to take into account the internal dynamics of the target and the influence of the pulse parameters in a simple way. The proposed approach is used both for the probability for the entire pulse duration, and for its dependence on the current time. In addition, the developed method is applied to generalize the simulation of the population kinetics of a quantum system to take into account the dependence of the photoprocess rate on time. It is also shown that our expression for the probability of excitation of a micro-target corresponds to the formula describing the energy loss of a non-monochromatic field in a dispersive medium and can be generalized on other EM processes.