Transversality, Morse functions, stable and unstable manifolds, Morse-Smale moduli spaces, the space of gradient flows, compactification of the moduli spaces of flows, Morse homology, applications.
Suggested books and references:
Michèle Audin, Mihai Damian, Morse Theory and Floer Homology, 2014, Springer-Verlag London.
J. Milnor, Morse Theory, Ann. of Math. Stud. 51, Princeton Univ. Press, Princeton, 1963..
L. Nicolescu, An invitation to Morse theory, http://www3.nd.edu/~lnicolae/Morse2nd.pdf.
M. Schwarz, Morse homology, Birkhäuser, Basel, 1993.
R. Cohen, Kevin Iga, Paul Norbury, Topics in morse theory, lecture notes, 2006.