  This chapter will go through the important nuclear reactions in stellar
evolution and explosions, passing through the individual stellar burning stages
and also explosive burning conditions. To follow the changes in the composition
of nuclear abundances requires the knowledge of the relevant nuclear reaction
rates. For light nuclei (entering in early stellar burning stages) the
resonance density is generally quite low and the reactions are determined by
individual resonances, which are best obtained from experiments. For
intermediate mass and heavy nuclei the level density is typically sufficient to
apply statistical model approaches. For this reason, while we discuss all
burning stages and explosive burning, focusing on the reactions of importance,
we will for light nuclei refer to the chapters by M. Wiescher, deBoer &
Reifarth (Experimental Nuclear Astrophysics) and P. Descouvement (Theoretical
Studies of Low-Energy Nuclear Reactions), which display many examples,
experimental methods utilized, and theoretical approaches how to predict
nuclear reaction rates for light nuclei. For nuclei with sufficiently high
level densities we discuss statistical model methods used in present
predictions of nuclear reaction cross sections and thermonuclear rates across
the nuclear chart, including also the application to nuclei far from stability
and fission modes.
