Project —Task Trees and Dependencies

"A project network is a graph (flow chart) depicting the sequence in which a project's terminal elements are to be completed by showing terminal elements and their dependencies.
... the project network shows the "before-after" relations.
The most popular form of project network is activity on node, the other one is activity on arrow.
The condition for a valid project network is that it doesn't contain any circular references." [Project network. Wikipedia]
The PERT chart example "Project management plan" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the solution "Seven Management and Planning Tools" from the Management area of ConceptDraw Solution Park.

"Project planning is part of project management, which relates to the use of schedules such as Gantt charts to plan and subsequently report progress within the project environment.
Initially, the project scope is defined and the appropriate methods for completing the project are determined. Following this step, the durations for the various tasks necessary to complete the work are listed and grouped into a work breakdown structure. Project planning is often used to organize different areas of a project, including project plans, work loads and the management of teams and individuals. The logical dependencies between tasks are defined using an activity network diagram that enables identification of the critical path. Float or slack time in the schedule can be calculated using project management software. Then the necessary resources can be estimated and costs for each activity can be allocated to each resource, giving the total project cost. At this stage, the project schedule may be optimized to achieve the appropriate balance between resource usage and project duration to comply with the project objectives. Once established and agreed, the project schedule becomes what is known as the baseline schedule. Progress will be measured against the baseline schedule throughout the life of the project. Analyzing progress compared to the baseline schedule is known as earned value management.
The inputs of the project planning phase include the project charter and the concept proposal. The outputs of the project planning phase include the project requirements, the project schedule, and the project management plan." [Project planning. Wikipedia]
The flow chart example "Project planning process" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Flowcharts solution from the area "What is a Diagram" of ConceptDraw Solution Park.