Explore the fundamental role of programming languages in the computer age through this 55-minute lecture by Dr. Peter Schachte from the University of Melbourne. Delve into the ubiquity of software in modern life and its impact on various sectors. Examine the importance of developing reliable software and the crucial role of programming language research in achieving this goal. Learn about program validation, software testing, and verification techniques. Investigate program analysis methods, including interval analysis and efficient relational analysis. Gain insights into programming language design, comparing imperative and declarative languages. Understand how compilers, analyzers, and verifiers utilize intermediate representations of programs.