This seminar is closely related to the framework of SFB TRR 227, therefore the involved postdocs, PhD and master students are recommended to participate. Basic approaches of ultrafast optical, nonlinear-optical, magneto-optical, and nonlinear-magneto-optical spectroscopies will be introduced and discussed. After going through the general optical background, various techniques will be discussed based on original papers as examples of their application. Particular focus will be made on state-of-the-art spin dynamics studies. The actual content will be to certain extent adjusted to the interest of participants. The seminar will be in online format, which assumes certain flexibility in choosing a next date/time. All people having an interest are welcome to contact me via alexey.melnikov@physik.uni-halle.de.