Ordered magnetic materials exhibit intriguing textures and defects that are stable for the topological reasons, which are exemplified by a domain wall in an easy-axis ferromagnet and a vortex in a planar ferromagnet. In this thesis, we study dynamics of these magnetic textures and topological defects in ferro- and antiferromagnets.Dynamics of magnetic textures in ferromagnets are described by the method of collective coordinates that focuses on soft modes of the system. The force can be exerted on textures by an external magnetic field, spin-polarized electric current, and a spin wave. As an example, dynamics of a domain wall in an easy-axis ferromagnet is studied under all three perturbations.Order parameter in antiferromagnets is the staggered magnetization. Slow dynamics of textures in the staggered magnetization is naturally described by the Hamilton dynamics of a few collective coordinates and their conjugate momenta that are defined in terms of the small uniform magnetization. We study the effect of the three out-of-equilibrium perturbations on magnetic textures as for ferromagnets. As an example, spin-wave driven dynamics of a domain wall in an easy-axis antiferromagnet is studied.Bloch points are topological defects. The simplest example is a diverging Bloch point with the magnetization of the unit radial vector, which is singular at the origin. The discrete nature of a magnetic lattice creates a periodic potential that can pin a Bloch point. The pinning force is of the order of the exchange constant, a few piconewtons in a typical ferromagnet(permalloy). A domain wall containing a Bloch point can have a sizable depinning field in the tens of oersted.
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