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PMBOK, WBS, and Gantt Charts Basics | IT Passport Exam Prep

April 26, 2026

A structured overview for the IT Passport exam of the global project management standard PMBOK, the work breakdown structure WBS, and the differences between Gantt charts and arrow diagrams for visualizing progress.

TagsIT PassportManagementProject Management

What is PMBOK?

PMBOK (Project Management Body of Knowledge) is a global standard guide for project management developed by the Project Management Institute (PMI) in the United States. It is systematized through a combination of 10 knowledge areas (Integration, Scope, Schedule, Cost, Quality, Resources, Communications, Risk, Procurement, Stakeholders) and 5 process groups (Initiating, Planning, Executing, Monitoring & Controlling, Closing). In the IT Passport exam, questions frequently ask you to select the correct "PMBOK knowledge area" or the "order of process groups."

What is WBS?

WBS (Work Breakdown Structure) is a diagram that hierarchically breaks down a project's deliverables and work into a tree structure from "large → medium → small." The terminal nodes are work packages (the smallest units of work), and the WBS dictionary clearly defines the responsible person and deliverables for each task.

How to Create a WBS (Frequently Tested)

The principle is to decompose the WBS based on deliverables, not processes. Additionally, the "100% rule" states that the sum of the decomposed work must exactly match the original scope without any excess or deficiency. Conducting reviews to prevent omissions or overlaps is also an important step confirmed in the exam.

Charts for Schedule Management

Gantt Chart

This chart uses a horizontal axis for time and a vertical axis for work items, representing the start and end of tasks with bars. It is ideal for visualizing progress, but its weakness is that it is difficult to directly represent dependencies between tasks.

Arrow Diagram (PERT Chart)

In this diagram, nodes represent events and arrows represent tasks. If the critical path (the longest path) is delayed, the entire project schedule is also delayed. Calculations for "earliest start time," "latest start time," and "float (slack time)" are frequently tested, so it is reliable to work through a simple diagram once.

Milestone Chart

This is a simple chart that only shows important milestones, such as release dates or review dates. You may be asked about the differences in its use compared to Gantt charts and arrow diagrams.

Key Points in the IT Passport Exam

The focus is on identifying terminology (differences between WBS and PERT, differences between Gantt charts and milestone charts) and calculation problems to find the critical path from a simple PERT diagram. Questions asking you to select "which knowledge area" a concept belongs to from PMBOK's 10 knowledge areas are also repeatedly tested.

Related Terms

Agile development is sometimes tested as an approach contrasted with PMBOK; details are explained in Agile Development and Scrum. ITIL is a standard for the operations phase, not projects, so check the differences in What is ITIL to avoid confusion.

Study Tips

The fastest way to learn is to distinguish them by purpose: WBS for deliverable-oriented decomposition, Gantt charts for visualization on a time axis, and PERT for dependencies and the longest path. Memorizing PMBOK's 10 knowledge areas together using acronym mnemonics makes them easier to remember.

Summary

If you can distinguish between the tools of "decomposition → visualization → tracking," you can reliably score points on the 1-2 frequently tested questions. For comprehensive practice on the Management domain, see Management Summary; for a full-length practice exam, go to Mock Exam.

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