This book presents the classical theorems about simply connected smooth
4-manifolds: intersection forms and homotopy type, oriented and spin
bordism, the index theorem, Wall's diffeomorphisms and h-cobordism, and
Rohlin's theorem. Most of the proofs are new or are returbishings of
post proofs; all are geometric and make us of handlebody theory. There
is a new proof of Rohlin's theorem using spin structures. There is an
introduction to Casson handles and Freedman's work including a chapter
of unpublished proofs on exotic R4's. The reader needs an understanding
of smooth manifolds and characteristic classes in low dimensions. The
book should be useful to beginning researchers in 4-manifolds.