This lecture covers the Z-transform inversion by complex integration, the zone of convergence, and the relationship with the Fourier transform in discrete time. It discusses properties of the Z-transform, including linearity, shifting, and oversampling. The lecture also explores the concept of semi-finite support for signals and the determination of the convergence radius. Emphasis is placed on understanding the behavior of signals with semi-finite support and the precise specification of the zone of convergence.