A Work Breakdown Structure (WBS) decomposes a project into smaller, manageable components -- phases, deliverables, and individual tasks -- making large or vague projects easier to estimate, assign, and track. Once tasks are identified, you sequence them by identifying dependencies: some tasks can run in parallel, while others (like 'design' before 'build') must happen in a strict order. A Gantt chart, named after engineer Henry Gantt, displays these tasks as horizontal bars along a timeline, showing start and end dates, overlaps, and dependencies at a glance. The longest chain of dependent tasks that determines the project's minimum possible duration is called the critical path -- any delay on it delays the whole project.