How to Discover Critical Path on a Gantt Chart

The PERT chart shows the logical connections and consequence of a set of tasks. PERT charts the time period for problem solving and the implementation plan for all activities along the critical path. The PERT chart is also known as a precedence diagram or project network diagram.
"The Program (or Project) Evaluation and Review Technique, commonly abbreviated PERT, is a statistical tool, used in project management, that is designed to analyze and represent the tasks involved in completing a given project. ...
PERT is a method to analyze the involved tasks in completing a given project, especially the time needed to complete each task, and to identify the minimum time needed to complete the total project.
PERT was developed primarily to simplify the planning and scheduling of large and complex projects. ...
A network diagram can be created by hand or by using diagram software. There are two types of network diagrams, activity on arrow (AOA) and activity on node (AON). Activity on node diagrams are generally easier to create and interpret." [Program Evaluation and Review Technique. Wikipedia]
The PERT chart is one of the Seven Management and Planning Tools (7 MP tools, Seven New Quality Tools).
The PERT chart template for the ConceptDraw PRO diagramming and vector drawing software is included in 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.