Weekend research talk: What is an L-function?

The next chapter of the RH Saga will aim to answer the question "What is an L-function?". As preparation for that chapter, perhaps you will enjoy this beautiful and well-paced talk by Ram Murty covering different notions of L-functions in a panoramic and historical overview, from the Riemann zeta function to the Langlands program. There is some introductory waffle and a presentation of the speaker before the talk itself starts around the 4-minute mark. It is one of the best introductory talks I have ever seen on L-functions in general.