  These are lecture notes, which summarize the current status of the
Semiclassical theory, as well as Monopoles, Instantons, Instanton-dyons and
Flux tubes. The emphasis is on QCD and QCD-like theories (deformed QCD),
although relevant points derived in Supersymmetric theories are also covered.
While the actual lectures on which the notes are based were delivered in the
fall 2018, the text evolved over the years and summarizes about 4 decades of
development. One recent point added is the so called Poisson duality between
monopoles and instanton-dyon approaches. It is made in a book format, with
extensive list of references. Large size of the text have lead to many
imperfections, which I hope to correct in future versions.
