  This is a redacted transcript of a course given by the author at Harvard in
spring semester 2016. It contains a pedagogical overview of recent developments
connecting the subjects of soft theorems, the memory effect and asymptotic
symmetries in four-dimensional QED, nonabelian gauge theory and gravity with
applications to black holes. The lectures may be viewed online at
https://goo.gl/3DJdOr. Please send typos or corrections to
<EMAIL_ADDRESS>