This lecture by the instructor covers the theory and applications of interest rate swaps, including the comparison between two-year placements and two one-year placements, arbitrage conditions, the term structure of interest rates, and the impact of interest rate expectations on the yield curve. It also discusses the concept of risk-free interest rate curves in Switzerland, variable and fixed-rate mortgages, and the calculation of spot rates for bond pricing. The lecture concludes with a practical example of using spot rates to calculate the net present value of a real estate project.