This lecture focuses on numerical methods for solving differential equations, particularly emphasizing the stability of these methods. The instructor begins by discussing the simplest method for solving first-order linear differential equations, introducing the concept of initial value problems. The lecture covers the formulation of the differential equation and the importance of initial conditions. The instructor explains the numerical approximation techniques, including the Euler method, and highlights the significance of stability conditions in numerical analysis. The discussion includes the implications of using implicit versus explicit methods, detailing how stability conditions affect the choice of method. The instructor provides examples and theoretical insights into error analysis, demonstrating how to calculate the error in numerical approximations. The lecture concludes with a discussion on practical applications of these methods in engineering and science, emphasizing the importance of understanding the underlying principles to effectively apply numerical techniques in real-world scenarios.