The work provides an overview on modern nuclear astrophysics by summarizing recent achievements in studies of light nuclei and thermonuclear processes at low and ultralow energies in the Universe. Special focus lies on mathematical methods and computer programs for calculating nuclear characteristics for thermonuclear reactions.

In this book, the authors consider briefly and simply all the major thermonuclear reactions which may take place in the stars at different stages of their formation and evolution. The authors provide an overview of possible reactions in three major thermonuclear cycles for stable stars of the Main Sequence and then indicate which processes will be considered and which ones will be analysed in the nearest future.