This lecture covers the proof of the non-vanishing of the Quadratic Dirichlet L-function and reviews basic properties of the Gamma function. The slides discuss various mathematical methods and concepts related to the non-vanishing of L-functions and the properties of Gamma functions, including the infinitude of primes, playing against transducers, and the Arnold-Mathematical Method. The lecture also delves into the Dirichlet class number formula, the Goldfeld proof, and the Gauss class problem. Additionally, it explores the Stirling's formula and the Euler reflection formula. The instructor presents an elementary proof and discusses the significance of the results obtained.