In this, the second online lecture we are making widely available, Ben Green introduces and delivers a short lecture on Primitive Roots, part of the Number Theory Lecture course for Second Year Undergraduates. We are making these lectures available (there are many more on this YouTube Channel via the Playlist) to give an insight in to the student experience and how we teach Maths in Oxford. All lectures are followed by tutorials where pairs of students spend an hour with their tutor to go through the lectures and accompanying work sheets. An overview of the course and the relevant materials is available here: https://courses.maths.ox.ac.uk/node/44147
