  In these lecture notes we will consider systems in which the motion of
electrons is confined to one dimension (1D). In these so-called quantum wires
electron-electron interaction effects play an important role because the
restricted dimensions enhance the scattering between the electrons and
completely destroy the quasi-particle picture. New density wave excitations
appear that are described by bosonic operators. Here, we will develop this
bosonic description, following a pedestrian approach which does not require any
previous knowledge in field theory methods. These notes therefore serve as a
detailed introduction into bosonization by carefully deriving the most
fundamental formulas.
