Two lectures on local riemannian geometry, $Spi{n}^{\text{C}}$ - structures and Seiberg - Witten equation

In the present text we discuss basic aspects of the Seiberg - Witten theory mainly focusing the attantion on some geometrical details which could make the introduction to the subject more illustrative. At the same time we list there natural problems arise in this framework mostly interesting to the author. This text could be regarded as additional remarks to any comlete course on the Seiberg - Witten invariants.