The document discusses the history and concepts of Critical Path Method (CPM) and Program Evaluation and Review Technique (PERT), which are network analysis techniques used for project management. CPM was developed by DuPont in the 1950s for chemical plant projects, while PERT was developed by the US Navy for the Polaris missile program. Both techniques use network diagrams of activities and their dependencies to analyze the critical path and schedule of a project. CPM uses deterministic activity times while PERT uses probabilistic times to account for uncertainty. The techniques help answer questions about project completion dates, schedules, budgets, and how to finish early.