In Critical Path Method (CPM), the early start (ES) and early finish (EF) dates concept is crucial. It represents the earliest start and end times for each project activity, assuming everything prior was completed as soon as possible. ES is calculated from the project start towards the finish, and EF is computed by adding the activity’s duration to its ES. Knowing these dates is vital for efficient project planning and avoiding unnecessary delays. Also, it facilitates flexible resource management.

Late Start (LS) and Late Finish (LF) dates indicate the latest possible times an activity can start and finish without delaying the overall project, respectively. Computed from the project end towards the start, they provide a deadline for each task. By comparing the LS and LF with the ES and EF, project managers can determine each activity’s ‘float’ or ‘slack.’ LS and LF are instrumental in identifying and managing potential problems and risks.

The Critical Path is the sequence of tasks that forms the longest duration allowing the project to be completed in the shortest time. Any delay in these tasks would directly result in a delay of the entire project. Therefore, they have zero 'float.' Decisive in the CPM, the critical path helps identify the tasks that should be closely managed and controlled to ensure the project's successful and timely completion.

Float, also known as slack, measures the amount of time that you can delay a task without causing a delay to other tasks or the project. Zero float tasks are on the critical path, while non-zero floats are off the critical path. This concept provides flexibility within the project schedule, allowing project managers to prioritize and reallocate resources if necessary and serves as a buffer against possible project delays.

Activity Sequencing involves identifying and organizing the dependencies between different tasks in a project. Understanding how these tasks relate is crucial for defining the project order and structure. In CPM, compiling these relationships in a logical sequence determines the project's overall flow and lays the foundation for devising the project schedule. This aspect helps project managers anticipate potential bottlenecks and plan resources and timelines strategically.

Project Network Diagrams are a type of flow chart and are primary tools for displaying the sequence of activities in a project. The main types of network diagrams used in project management are the PERT and Gantt charts. These visuals help to establish the timeline, identify dependencies, and pinpoint critical paths. In the context of the Critical Path Method, the diagram is used to identify the longest path of planned activities to the end of the project, and the earliest and latest that each activity can start and end without making the project longer.

Forward pass is a technique used to estimate the early start and early finish dates for the uncompleted portions of all network activities. This is done by moving forward through the project's network diagram, with the objective of identifying the project timeline. It's an important concept in understanding the Critical Path Method, as it lays the foundation for determining slack or float periods, as well as identifying the critical path.

In contrast to the forward pass, the backward pass is a project network diagram technique used to determine the late start and late finish dates of unfinished activities. It works by moving backward through the network diagram. This method helps in pinpointing the tasks that could be delayed, without affecting the project's end date, which is critical in project scheduling and risk management.

Project duration is the time between the start and the completion of the project. It is a crucial element of the Critical Path Method. This method aims at determining the shortest possible project duration by optimizing the sequence of tasks. It does so by highlighting activities that directly impact the project timeline (i.e., those on the critical path). This information can then be used to better manage project schedules and allocate resources more efficiently.

In the context of the Critical Path Method, Lead time is the time that can be saved on the successor activity by beginning the predecessor task early. On the other hand, Lag time is a delay between tasks that must be observed for technological or process-related reasons. Both Lead and Lag time are essential considerations when identifying the critical path, optimizing schedules, and assessing project risks.