This lecture on Z-transform explains how to convert discrete-time signals from the time domain to the Z-domain for easier analysis and problem-solving. It covers the definition, formula, region of convergence (ROC), properties, and practical applications in signal processing, control systems, and digital filter design. Students will learn how to solve difference equations, analyze system stability, and apply Z-transform techniques in real-world engineering problems. Perfect for Maths 3 syllabus and competitive exam preparation.