X-ray absorption (XA) spectroscopy enables us to probe the electronic structure and magnetic ordering in, for example, thin-film systems. The photon–matter interaction contains both nonresonant and resonant terms, but only the latter have a strong sensitivity to the spin and orbital moments of the valence shell. Selection rules in XA provide us with a probe to study the local magnetic ground state. The branching ratio of the spin–orbit split core-level spectra is proportional to the ground-state spin–orbit interaction and can also provide a measure of the spin state. The angular dependence of the X-ray magnetic circular dichroism (XMCD) can be described as a sum over an isotropic and an anisotropic contribution, where the latter is linearly proportional to the axial distortion due to strain. The anisotropic properties of magnetic materials are essential to maintain the preferred magnetization direction. These properties, such as the magnetocrystalline anisotropy energy (MAE), have their origin in the orbital moment anisotropy, which can be studied element-specifically using angular-dependent XMCD. Alternatively, the MAE can also be studied using X-ray magnetic linear dichroism (XMLD).