|  Define & Plan activities  ||    Planning|
|  Sequence activities  ||    Planning|
|  Estimate resources  ||    Planning  |
|  Estimate duration of activities  ||    Planning  |
|  Develop schedule  ||    Planning  |
|  Control schedule  ||    Monitoring & Controlling  |
This knowledge area is concerned with estimating the duration of the project plan activities, devising a project schedule, and monitoring and controlling deviations from the schedule.
"Hours are like diamonds, don't let them waste... Time waits for no one, no favours has he... Time waits for no one, and he won't wait for me"   Jagger/Richards
Activity definition consists of decomposing or breaking down the work to reach a level that can be easily estimated and managed.
Network diagrams are used to display activities and their dependencies. There are two type of network diagrams:
Dependencies may exist for activities which will impact when they can be scheduled. Types of dependencies between activities can be Mandatory, External, or Discretionary.
Leads & Lags are also important concepts to understand for scheduling activities to account for dependencies.
This process involves estimating internal / external human resources (including vendors), as well as equipment and materials. It takes into account the skill sets and number of resources required for the work effort.
PERT is a network model that allows for randomness in activity completion. From PMBOK, PERT uses a weighted average duration estimate to calculate activity durations. PERT Formulas
Critical Path - longest duration path through a network diagram. The Critical Path is the shortest possible time it will take to complete the project.
CPM (Critical Path Method) - From PMBOK, CPM "calculates a single, deterministic early start and finish date for each activity based on specified sequential network logic and a single duration estimate."
Float - amount of time a task can be delayed without delaying the project. Also known as slack. Note that tasks on the critical path have zero float.
Float = LF - EF = LS - ES
LF = Late Finish
EF = Early Finish
LS = Late Start
ES = Early Start
This process involves monitoring project status and controlling changes to the project schedule. Progress reporting is used to communicate the overall project schedule to stakeholders.