Since 2002 Perimeter Institute has been recording seminars, conference talks, and public outreach events using video cameras installed in our lecture theatres. Perimeter now has 7 formal presentation spaces for its many scientific conferences, seminars, workshops and educational outreach activities, all with advanced audio-visual technical capabilities. Recordings of events in these areas are all available On-Demand from this Video Library and on Perimeter Institute Recorded Seminar Archive (PIRSA). PIRSA is a permanent, free, searchable, and citable archive of recorded seminars from relevant bodies in physics. This resource has been partially modelled after Cornell University's arXiv.org.
In these two lectures I will present on overview of topological string theory, starting with the basic concepts and continuing to the most recent developments. Aspects that will be covered are: closed and open strings, Gromov-Witten theory, matrix models, quantum crystals, and special holonomy manifolds. I will end with some more speculative thoughts about the non-perturbative definition of (topological) string theory and quantum geometry.