# Understanding the timeline in five minutes

The timeline is the time grid that fills the right-hand part of the editor. Here's the vocabulary and the ribbon's buttons, as they really appear in the application.

## The vocabulary

- **A phase** groups rows ("Phase 1" when a schedule is created). It collapses and expands.
- **A row** carries the blocks of one activity, resource, or owner.
- **A block** is a dated task: a color, a label, a duration in working units.
- **An icon** (or **milestone**) is a one-off symbol placed on a precise date rather than a duration — right-clicking an empty cell offers "Insert a block here" and "Insert an icon here".
- **A link** connects two blocks and states their order: this five-minute guide doesn't go further — the distinction between a *hard* link (which pushes) and a *soft* one (which never pushes) is the subject of the guide *[The timeline: blocks, links and milestones](/docs/en/guides/timeline-blocs-et-dependances/)*.
- **The calendar** decides which days count as working days — it's what fixes a block's real duration. See the guide *[The calendar, closures and absences](/docs/en/guides/calendrier-fermetures-absences/)*.

## The "Summary" bar

Right above the grid, a collapsible line states at a glance: the number of rows, the number of blocks, the period covered and the number of working units it represents, and the number of dependencies (with any that are violated, if there are any).

## The ribbon, button by button

Left to right, as observed in the application:

| Button | What it does |
| --- | --- |
| Undo / Redo | Undoes or redoes the last gesture — a Ctrl+Z / Ctrl+Y shortcut also exists. |
| Zoom out / Zoom in | Changes the display grain (day, week, month…) ; the current grain shows between the two buttons. |
| Today (T) | Recenters the view on today's date, marked by a vertical line in the grid. |
| Go to a date | A date field: the view jumps straight there. |
| Overview | Adjusts the zoom so the whole schedule fits on screen. |
| Search and filter (Ctrl+F) | Opens the search-and-filter panel, to keep only certain rows. |
| Critical path | Shows or hides the critical path (the blocks whose one-day delay pushes back the schedule's end). |
| Mini-map | Shows a reduced view of the whole schedule, with the frame of what's currently visible. |
| Printable preview (Ctrl+P) | Opens the print / image-export preview. |
| Versions | Opens the schedule's version history (daily, or taken by hand). |
| Settings | Opens the settings modal: the time unit, active days, working hours, the reference date, the legend, printing. |

## What gets painted in the grid

- Weekends (or more generally inactive days) are shaded.
- A block displays in its color, with its label if it fits within its width.
- A color or icon used on a block automatically enters the legend, at the bottom of the screen — you don't have to declare anything separately.

## And next

This guide gives just enough vocabulary to find your way around. To go further on a specific point, the task guides each detail one gesture: *[The grid and columns](/docs/en/guides/grille-et-colonnes/)*, *[The legend and the filter](/docs/en/guides/legende-et-filtre/)*, *[A block's actions and its derived progress](/docs/en/guides/actions-et-avancement/)*, etc. — see [Task guides](/docs/en/guides/).