Baseline
The version of the plan everyone agreed to before the work started — kept frozen so you can see how far reality has drifted from it.
the plain-english glossary
Project words, translated
Planning has a vocabulary problem: simple ideas wearing certified jargon. Here are the 15 words that actually matter on a timeline, defined the way you'd explain them out loud.
From the studio behind ganttchart.ai. If you'd rather learn by doing, start with the guide: How to turn a plain-English plan into a Gantt chart. Or see the words in action in five worked Gantt chart examples.
Buffer
Time deliberately added to a plan to absorb slips. The difference between a plan that survives contact with reality and one that doesn't.
Critical path
The chain of dependent tasks that sets the earliest possible finish date. If anything on it slips, the end date slips with it — everything else has room to move.
Deliverable
The concrete thing a task or project hands over when it's done — a launched site, a signed-off design, a working feature. A result, not an effort.
Dependency
A link between two tasks saying one can't start (or finish) until the other does. Dependencies are what turn a list of tasks into an actual plan.
Duration
How long a task takes in calendar time, start to finish — which is not the same as how much work it contains.
Finish-to-start
The most common dependency type: task B can't start until task A finishes. If you'd say 'then' out loud, you mean finish-to-start.
Gantt chart
A chart that shows a project as horizontal bars on a calendar — one bar per task — so you can see what happens when, what overlaps, and what's waiting on what.
Lead time & lag time
Adjustments on a dependency between tasks: lead lets the next task start early and overlap, lag forces a wait after the previous one finishes.
Milestone
A zero-length moment that matters to people outside the work — a launch, a review, a handoff. On a Gantt chart it's a diamond; in an email it's a date.
Scope creep
The plan quietly growing while the deadline stays put — one small, reasonable addition at a time, none of them decided out loud.
Slack (float)
How long a task can slip before it delays anything else. Tasks on the critical path have none; everything else has some, and knowing how much is free information.
Task
One chunk of work on the plan, named the way your team talks and sized for the room — 'Design' is one bar, even if it's forty tickets.
Timeline
Any picture of events laid out against time. Every Gantt chart is a timeline; not every timeline is a Gantt chart — the difference is whether the bars know about each other.
Work breakdown structure
The exercise of splitting a project into pieces small enough to plan — the outline you write before any chart can draw the bars.
Missing a word that confuses your meetings? Tell the trolls: suggest a term.
Words in, chart out
You don't need the vocabulary to make the chart. Describe your project in plain English and ganttchart.ai draws the bars, arrows, and diamonds for you.
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