The document summarizes the data structures and algorithms used in a program that manages an agenda of events and tasks. It involves two main classes: events, which have set times, and tasks, which have a duration and priority that can be updated. The core algorithm takes tasks of given durations and priorities and schedules them as agenda events, while another algorithm adjusts timings when tasks are progressed or completed. An example is given of scheduling five tasks of varying durations and priorities within a six hour timeline to illustrate the complexity involved in prioritizing by both duration and priority.