In this thesis the effect of Autler-Townes splitting is revisited and the dynamics of a 2- and 3-level quantum systems, exhibiting this effect, is studied. This effect is a special case of the Stark effect, where the spectral lines of an atom are modified due to an external driving electromagnetic field. Two different articles, describing the Autler-Townes splitting, are studied, where one solves the time-dependent equations of the semi-classical model and the other studies the time-independent Hamiltonian for the system, which is described completely quantum mechanically. In our work, we proceed by employing the semi-classical model but transforming the Hamiltonian into a time-independent form, which makes the model easier to study. Subsequently, we also study the atom as an open quantum system and investigate the effect that the decay of an atom to a vacuum field has on the Autler-Townes splitting. Throughout the thesis, we present the density matrices, and hence the time-evolution of the dynamics, in the Bloch-vector description in an attempt to understand the geometrical nature of the dynamics and, in effect, the Autler-Townes phenomenon.