Writing

The editor and the manuscript: scenes, chapters and parts; notes; find and replace; formatting; comments and suggestions.

Write, Outline and Preview

The editor has three ways of looking at your book, and you can flip between them at any time from the Write · Outline · Preview switch in the toolbar. This page explains what each is for.

Work bar screenshot.png

Screenshot: the toolbar's Work group, with the Write · Outline · Preview switch and the Notes, Codex and Listen buttons beside it.

Write

Where you'll spend most of your time: one scene at a time, on the page, as it will print. Pick a scene in the manuscript list on the left and write.

Outline

The whole book on one screen, as a plan. Each chapter shows its title and a line for what happens in it; under it, each scene has a row with its title, point of view, when and where it happens, a status (Draft, Revised or Final), a short synopsis, and its word count.

Everything in the outline can be typed into directly, so it works however you plan:

You can also rearrange the book here:

Click a scene's title to open it in Write. Nothing in the outline prints; it's yours.

Outline Screenshot.png

Screenshot: the Outline view with two chapters, their synopses, and the scene rows showing POV, When, Where, status and word counts.

The outline beside the page

If you'd like the outline in view while you write, turn on Outline at the side from the Show menu in the toolbar. A slimmer version sits in a rail beside the page.

Preview

Your pages exactly as they'll print, many at a time, like zooming out in a word processor to see the shape of things. It's the same typesetting the print PDF uses, so a chapter opening, a picture or a stray line at the end of a chapter looks here just as it will in the book.

Preview takes a moment to set the pages, especially for the whole book. While it works, it tells you about how many pages there are and roughly how long they'll take, with a clock of the time so far. The time is a guess the first time, and learns from how fast your previews have actually set.

A line or two alone at the end of a chapter

When the whole book is previewed, a Fit bar lists any chapter that ends with a line or two alone on its last page, with a few paragraphs that could pull it back (Tighten) or push it on (Loosen). Click one and Write sets that paragraph a hair tighter or looser, sets that chapter again, and puts it back into the pages in front of you in a few seconds. The chapter's line in the Fit bar then says whether it worked.

Organize chapters and scenes

This page is about the shape of your book: adding chapters and scenes, moving them around, grouping chapters into parts, and putting aside the ones you're not sure about. All of it happens in the manuscript list down the left side of the editor.

Screenshot: The manuscript list Screenshot: the manuscript list on the left, with a chapter open showing its scenes, and the gear menu beside a chapter.

How the list works

Your book is a list of chapters, and each chapter holds one or more scenes. Click a chapter to open it and see its scenes; click a scene to write in it. The number at the right of each row is its word count.

Point at a row and a small menu appears beside it—a gear for a chapter, three dots for a scene. Almost everything on this page starts from one of those two menus. (On a phone or tablet the menus are always showing.)

Add chapters and scenes

To add a chapter, click the + beside Manuscript, or + Chapter at the bottom of the list. A new chapter arrives with one empty scene, ready to write in. If the chapter before it has header fields (a date line or a point-of-view line, say), the new chapter gets the same fields, empty, so you don't have to add them again.

To add a scene, open the chapter's gear menu and choose Add a scene. The new scene goes at the end of the chapter.

Rename a chapter or scene

Choose Rename chapter or Rename scene from its menu. A chapter's title is the one that prints; a scene's title is for you—it shows in the list and the outline, but never in the book.

Move things around

Drag and drop

Drag a chapter up or down the list to move it. Drag a scene to move it within its chapter, or into a different chapter altogether—the space opens up where it will land.

Or use the menus

If dragging is fiddly, Move chapter up and Move chapter down (or Move scene up and Move scene down) do the same thing one step at a time.

Renumber your chapters

Moving a chapter doesn't change its number on its own—that way a chapter you're trying out in a new place keeps its name while you decide. When the numbers no longer run in order, a note appears at the top of the list: Chapter numbers are out of order. Click Renumber there, or choose Renumber chapters from the … menu beside Manuscript. Chapters without a number, like a prologue or an interlude, stay unnumbered, and the count skips them.

Merge two scenes

Sometimes two scenes turn out to be one. From the scene's menu, choose Merge into the scene above or Merge into the scene below. The text joins its neighbor, with any comments and suggestions still attached where they were. The neighbor keeps its own title, point of view, date, place and status; the two synopses and sets of notes are joined together.

You won't lose anything. Before the merge, the neighbor's text is saved in its history, and the scene you merged is archived rather than deleted. There isn't an "unmerge," though—restoring the archived scene brings back its text as a separate scene, alongside the merged copy. (Splitting the scene again, below, is usually the easier way back.)

Split a scene in two

Put your cursor where the new scene should begin, then choose Split the scene here from the Paragraph menu, or press Ctrl+Shift+Enter (Cmd+Shift+Enter on a Mac). Everything from the cursor on becomes a new scene right after this one, and it opens so you can carry on.

The new scene starts with the same point of view, date, place and status. Its title and synopsis are empty for you to fill in, and the scene's notes stay with the first half. Comments and suggestions go wherever their words went.

Nothing is lost here either: the scene as it was before the split is kept in its history, labelled Before a split.

Parts

Parts (or acts, if you prefer) group your chapters. Each part prints on its own page, with a number line over its title, and the list groups its chapters under it. Chapter numbers carry on from one part to the next.

Turn parts on

Parts are off until you want them. Open Chapter header setup (beside Manuscript) and find the Parts card. Set Use parts to On. While you're there, Called chooses between Part and Act, and Number reads as sets how the number prints.

If you turn parts off later, your parts are kept—they just stop showing and printing until you turn them back on.

Screenshot: The Parts card Screenshot: the Parts card in Chapter header setup, with Use parts set to On.

Add a part

With parts on, the + beside Manuscript asks whether you'd like a chapter or a part, and there's a + Part button at the bottom of the list too. Give the part a number, a title, or both. The window shows you how the number line will print.

Put chapters into a part

Drag a chapter into a part, or out of it. To add a fresh chapter straight into a part, choose Add a chapter here from the part's menu. To move a chapter out without dragging, choose Take out of its part from its gear menu. Drag a part itself and its chapters come along with it.

Change or remove a part

From the part's menu, Edit part changes its number or title. Remove part takes away the part but not its chapters—they stay right where they are, no longer in any part. It asks before it does anything.

If your parts end up out of order, Renumber parts in the … menu beside Manuscript puts their numbers back in sequence.

Archive a chapter or scene

Archiving puts a chapter or scene aside. It disappears from the list and from your book—it won't print, and its words don't count—but nothing is lost, and you can bring it back whenever you like.

Choose Archive chapter or Archive scene from its menu. To see what you've put aside, choose Show archived from the … menu beside Manuscript; archived rows appear, dimmed. Choose Restore chapter or Restore scene to bring one back, and Hide archived when you're done.

Delete for good

Only something you've archived can be deleted. With archived rows showing, its menu offers Delete chapter for good or Delete scene for good. It asks first, because this one can't be undone. Archiving is usually the better choice—an archived scene costs you nothing.

Who can do this

Owners and co-authors can reorganize the manuscript. Editors can write and suggest but don't see these menus, and readers only read. For more, see What each role can do.

Format your text

Write keeps formatting simple on purpose: you mark what the words mean—emphasis, a link, a line in another hand—and the page setup decides how it looks. This page covers the handful of things you'll use.

The selection bar

Select a few words and a small bar appears just above them.

Screenshot: the selection bar over some selected words Screenshot: a few words selected in a scene, with the selection bar above them showing bold, italic, Aa, link and Comment.

On a Mac, use Cmd wherever these say Ctrl.

Paragraph styles

Most paragraphs are ordinary body text, indented as your page setup says. For the others, put the cursor in the paragraph (or select several) and open the Paragraph menu in the toolbar:

The same menu inserts a text-message exchange.

Line breaks

Enter starts a new paragraph. Shift+Enter breaks the line without starting a new paragraph—for a poem, an address, the lines of a song.

Scene breaks

You don't type these. Each scene is its own page in the editor, and the book prints your scene-break ornament between them. To break one scene in two, put the cursor where the second should begin and choose Split the scene here from the Paragraph menu (or press Ctrl+Shift+Enter); see Organize chapters and scenes.

A stray line at the end of a chapter

Sometimes a chapter ends with one lonely line at the top of a page. The Paragraph menu has a fix under Fit, for a stray line: on a paragraph on the page before, choose Tighten a line, which sets its letters and spaces a hair closer so it may run one line shorter. Check in Preview; if it didn't quite do it, try another paragraph. Loosen a line does the opposite. The nudge is marked faintly in the margin of the editor and is invisible in the book.

What about fonts and sizes?

There are none in the editor, and that's deliberate. The font, size, spacing and indents of the whole book are set once, in Page setup, so every chapter matches. See Page setup: the basics.

Put a text-message exchange in a scene

What this is for

Characters text each other, and a page of "Where are you?" she typed gets old fast. Write can set an exchange the way readers see it on their own phones—bubbles, yours on the right and theirs on the left—and print it that way in the paperback and the ebook, on the same line grid as the prose, so nothing drifts. There are four looks to choose from, and the exchange is still words: it's searched and counted like any paragraph, and in Suggesting a changed bubble is proposed whole (see Suggest changes instead of making them).

Adding one

  1. Put the cursor in the paragraph the messages should follow.
  2. Open the Paragraph style menu in the toolbar and, under Insert, choose Text messages.
  3. An exchange appears with one empty bubble on the right—that's you, or rather the character whose phone the reader is looking at. Type the first message.
  4. Press Enter for the next message. It goes to the other person, and Enter again comes back to you, so a back-and-forth is just typing and Enter. To leave the exchange and get back to prose, press Enter on an empty bubble.

Above the first bubble is a field for who the messages are with—a name, or leave it empty for no header—and beside it the style. The × on the right takes the whole exchange out. If that was a slip, Ctrl+Z (Cmd+Z on a Mac) brings it straight back.

Screenshot: a text-message exchange in the editor

Screenshot: a text-message exchange in the editor, with a few bubbles on each side, the field for who the messages are with and the style menu above the first bubble, and the × on the right.

Who's talking

Hover a bubble, or put the cursor in it, and a small tag appears at its shoulder saying who sent it. Click the tag to change the sender: the people already in the exchange are listed, and there's a box at the bottom for someone new. More than one other person makes it a group chat, and their names print above their bubbles the way a phone does.

Screenshot: the sender tag's menu

Screenshot: the sender tag's menu open on a bubble, listing the people in the exchange with the pencil and colour swatch beside each name, the box for someone new at the bottom, and Pause before it.

The pencil beside a name in that menu renames the person throughout the exchange—handy when you started with a placeholder. A name you no longer use disappears on its own once no message is from them.

Taking a message out

Open the sender tag on the message and choose Delete this message. The cursor moves to the message before it. If it's the only message, the whole exchange goes with it, and the menu says so before you click. An empty bubble goes with Backspace, too.

A pause

When time passes between two messages—she doesn't answer for an hour—open the sender tag on the later message and tick Pause before it. The bubble sets a line apart from the one above, which is how readers see a gap on a phone.

The four styles

Each exchange can choose its own style from the little menu beside its header, or follow the book's default. The default lives in Chapter header setup, under Messages, so a whole series of holo exchanges doesn't need telling one at a time.

Colours, for colour print and the ebook

By default everything is set in greys, which prints well in black and white. If you're printing in colour, or want the ebook to look like a real phone, give each person a colour: click the swatch beside a name in a sender tag's menu, or set them all at once under Messages in Chapter header setup (me is the reader's side). Phone uses the colour as the bubble's fill; Holo and Torn paper as the ground, with the bar and edges a few shades darker; Terminal as the ink. If a colour is dark, the type goes white on it by itself. Colours are per book, and names match in any case.

Your own line under the header

In the same Messages section you can choose a picture to print under the name the exchange is with—a line, a flourish, a small emblem—in place of the style's rule or filigree. It takes the same Height, Width and Air settings as the other decorations (see Choose a scene-break ornament in the decorations book), and the stock library has a few header lines drawn for the purpose.

In print and the ebook

The exchange prints on the grid: every bubble is a whole number of lines tall, so the prose after it lands where it should. A long exchange breaks across a page between messages, never through one. In the ebook the bubbles follow the reader's font size and go light-on-dark in night mode.

Find and replace

This page shows you how to find a word or phrase—in the scene you're in, the chapter, or the whole book—and how to change it everywhere at once when a name or a spelling changes.

Open the find bar

Press Ctrl+F (Cmd+F on a Mac). A small bar floats over the top of the page, the way a browser's find does, so your text doesn't jump around. Type what you're looking for in Find, and every match lights up.

Screenshot: The find bar Screenshot: the find bar over a scene, with a word typed, matches highlighted, and the Scene/Chapter/Book choice showing.

Where it looks

For Chapter and Book, the matches are listed down the side, grouped by scene, with a count of how many there are and in how many places. Click one to go straight there. If there are a great many, the list shows the first 500 and says so—search for something a little more specific to see the rest.

Narrow it down

Two small buttons beside the box make the search pickier:

Replace

Press Ctrl+H to open the bar with a second row, Replace with, or click the small arrow at the left of the bar to show it.

Replacing in the open scene works like typing: Ctrl+Z undoes it.

Replacing across the chapter or book

A replace that reaches beyond the open scene always asks first. It tells you how many matches it found, what it will change them to, and how many scenes it will touch, so you can be sure before anything happens. When it's done, a note in the bar says how many it changed.

A couple of things it leaves alone on purpose:

When someone else is searching

Everyone on the book can find. Co-authors can replace just as you can. When an editor uses replace, their changes arrive as suggestions for you to accept or reject, like the rest of their edits. Readers see the find bar without the replace row. See Review suggestions and comments.

Keep notes beside your book

This page is about notes: the reminders you leave on a scene or chapter, and the longer documents—research, a to-do list, a scrap of worldbuilding—you keep beside the book. None of it ever prints.

Open your notes

Click Notes at the top of the editor. A panel opens on the right with three tabs: Scene, Chapter and Book. Click Notes again to close it.

Screenshot 2026-10-14 173646.png

Screenshot: the notes panel open, on the Book tab, with a few lines of notes typed in.

Notes on a scene or chapter

The Scene tab is a scratch pad for the scene you have open—what still needs doing, what to check, what you were thinking when you stopped. The Chapter tab is the same for the whole chapter: "cut the second argument," "check the date against book 3." Type, and it saves as you go.

These notes travel with their scene or chapter, so when you open a different scene, the panel shows that scene's notes instead.

The book's notes

The Book tab holds whole documents. Click + New note to start one; it opens in the middle of the screen, in a wide editor with all the usual formatting, and you can give it a title at the top. Click a note in the list to open it again, and drag the list into whatever order suits you.

Tags

Under the title, add a few tags—character, place, plot, or any word you like. Once your notes have tags, they appear as small buttons at the top of the list, each with a count. Click one to show only those notes; click it again to see them all. Over time this becomes a small bible for the book that you can sort through.

Turn a note into a codex entry

If a note about a character or place deserves a proper home, click Make this a codex entry at the top of the note. It becomes an entry in your universe's codex, and the note is set aside, marked codex, with a link to the entry. See Notes that become codex entries.

Archive or delete a note

Archive note sets a note aside without losing it. Archived notes gather under Show archived at the bottom of the list; click Restore beside one to bring it back.

Delete note removes it for good. It asks first, and suggests archiving instead if you'd like to keep the text.

Who sees your notes

Everyone you've invited to the book can read its notes, so they're a good place for things your co-author or editor should know. Owners and co-authors can write and change them.

If you've connected an AI assistant to Write, it can read your notes and add to them too—a handy place for it to leave research or a list of things it noticed. See Working with an AI.

Suggest changes instead of making them

This page is about the Writing and Suggesting switch at the top of the editor. In Writing, what you type goes straight into the book. In Suggesting, every change you make is marked as a suggestion instead, to be accepted or rejected later—handy when you're revising a co-author's chapter, or you want to try a cut without committing to it.

Switch modes

At the top of the editor, click Writing or Suggesting. That's all it changes: what your next keystroke does. Nothing you've already written is touched.

On a phone, the choice sits in the header as Write, Suggest and Outline.

Screenshot: The Writing and Suggesting switch Screenshot: the top of the editor with the Writing / Suggesting switch, Suggesting selected, and a suggested change in the text below.

Write remembers your choice for each book, in this browser, so if you like to revise in Suggesting, it'll be waiting that way next time.

What a suggestion looks like

While you're suggesting, words you add are underlined and words you delete are struck through rather than removed, all in your color. Keep typing and your changes in one spot stay together as a single suggestion—backspacing over a sentence is one suggestion, not forty.

If you change your mind about something you suggested, delete it: removing your own suggested words takes them away for real.

In a text-message exchange

Inside an exchange, a suggestion is a whole bubble rather than single words. The moment you change a bubble—type in it, change who sent it, add or remove a pause—the bubble as it was stays put, faded and struck through, and your version appears just below it, ringed in your color. Keep typing and you're editing that same new bubble; there's only ever one copy.

A struck bubble can't be typed in—clicking one points the review rail at it instead. Who the exchange is with and its style still apply right away, like a paragraph style, so editors can't change those.

In the review rail, a changed bubble reads as the message with the words that changed marked, and accepting keeps your version while rejecting brings back the original.

Screenshot: a suggested change in a text-message exchange Screenshot: an exchange in Suggesting with one bubble struck through and faded, the new version ringed in color below it, and the review rail showing "changed a message."

What isn't tracked

Suggesting is about the words. A few things still happen right away, even in Suggesting:

Your reviewer still sees every word that changed; it's only the shape around the words that goes in as you make it.

Editors always suggest

Someone you've invited as an editor works in Suggesting all the time; their Writing button is greyed out, with a note that editors suggest and the author accepts or rejects. That way their whole pass comes to you as changes you can review one by one. (Because paragraph styles aren't tracked, editors can't change those—they can leave a comment instead.)

Reviewing what's been suggested

Suggestions—yours, an editor's or an AI's—are listed in the review rail on the right, where you accept or reject each one. See Review suggestions and comments.

Change how the editor looks

This page covers the ways you can make the editor comfortable to sit with for a long session: light or dark, the color of the room, a dark page to write on, and whether you see your words as the printed page or as one long column.

None of this changes your book. It's all about your screen.

Light, dark and the colors

Click the small half-filled circle in the toolbar to open Appearance.

You can pick a light theme and a dark theme both, and Auto will switch between them as your computer does.

Screenshot: The Appearance menu Screenshot: the Appearance menu open in the editor, showing Appearance, Light theme, Dark theme, Layout and Dark page.

The same across Author Tools

Your appearance choices are saved for all of Author Tools, not only Write. Set Dark and Slate here, and the other Author Tools apps that offer these settings will open the same way. (The dark page and the layout are Write's own.)

A dark page

The colors of the screen and the color of the page you write on are separate choices. Someone who likes a light screen but finds a white page glaring after a few hours can have both. Turn on Dark page—it's at the bottom of the Appearance menu, and in the Show menu too—and your page goes dark with light text.

Until you choose, the page follows the rest of the screen: dark when Write is dark. Once you flip it yourself, it stays the way you set it. Your book still prints on white paper, of course; Preview always shows the real thing.

Print format or full width

Layout (in the Appearance menu, and in its own Layout menu in the toolbar) chooses how your manuscript sits on the screen:

Your words are the same either way; switch as often as you like.

Zoom

In print format, the – and + beside the percentage in the toolbar make the page smaller or larger. Holding Alt while you scroll does the same. (Full width doesn't zoom; it fills the space you give it.)

The Show menu

Show in the toolbar turns a few helpers on and off. Each one is remembered.

Listen to your book read aloud

This page is about Listen, which reads your book aloud a sentence at a time while you follow along. Hearing your words is one of the best ways to catch a clunky rhythm, a repeated word or a missing one—and as you listen, you can mark each spot that needs work without stopping.

Start listening

Put your cursor where you'd like to begin, then click Listen in the toolbar. A small bar appears at the top of the page and the reading starts from the cursor. The sentence being read is highlighted, so you can follow along.

It carries on from scene to scene to the end of the book, so you can sit back and listen to a whole chapter.

Screenshot: The listen bar Screenshot: the listen bar at the top of a scene, with a sentence highlighted on the page and a note typed in the mark box.

The controls

The keys work while the listen bar is the thing you last clicked.

Mark a spot

When you hear something that needs another look, click Mark (or press M). Write leaves a comment on the sentence being read, and the reading carries on. If you'd like to say what bothered you, type a few words in the box beside Mark first; or just mark it and keep going.

Your marks collect in the review rail on the right, alongside any other comments, so when you're done listening you have a list of every place your ear caught. See Review suggestions and comments.

What it reads

Listen reads your scene as it would print with every suggestion accepted: suggested new words are read, and words a suggestion is striking out are skipped.

About the voices

The voices come from your own browser and computer, so nothing you've written is sent anywhere to be read, and it costs nothing. It does mean the voices vary from one device to another—Edge, Chrome and Safari all have good ones. If your browser has no voices at all, the listen bar will say so.

Go back to an earlier version

This page is about History: the earlier versions of each scene that Write keeps for you, how to look at one and see what's changed since, how to put a scene back the way it was, and how to mark a milestone for the whole book.

You don't have to do anything to make versions. Write saves them as you go.

Open History

Open a scene, then click History in the toolbar. A panel opens on the right with two lists: This scene, the scene's versions with the newest at the top, and Milestones for the book.

Each version shows when it was made, its word count and who was writing. A few carry a small label: Before a restore, Before a split or Before a merge mark the moment just before one of those happened, and a milestone's name shows on the versions it kept.

Screenshot: The History panel Screenshot: the History panel beside a scene, with a few versions listed, one carrying a milestone's name, and two milestones below.

Look at an earlier version

Click a version. It takes the place of your page, and the bar above it says when it's from. Anything that has changed since is marked:

So you can read it as it was and see at a glance what you've done to it. Click Back to writing (or Now at the top of the list) to return to your page. Nothing changes just from looking.

Screenshot: An earlier version Screenshot: an earlier version open in the middle, with struck and underlined words, and the Back to writing and Restore this version buttons above it.

Put a scene back

While you're looking at a version, click Restore this version. The scene goes back to exactly that text.

You can't lose anything this way. Before it restores, Write keeps the scene as it was a moment ago as a version of its own, labelled Before a restore, so if you change your mind, restore that one.

Just one passage

If you only want back a paragraph you cut, there's no need to restore the whole scene. Open the old version, copy the passage, click Back to writing, and paste it where it belongs.

Milestones

A milestone is a name for a moment in the whole book: "Sent to Jill," "Before the line edit," "Draft two." It keeps every scene just as it is right then, so later you can find that moment in any scene's history.

To make one, click + Save a milestone under Milestones, give it a name (and a note, if you like), and click Save milestone. It's worth doing before you send the book out, or before a big round of changes.

To take a milestone away, point at it and click Remove. Your scenes don't change; the name just comes off their history.

What Write keeps

Who can do this

Everyone on the book can open History and look at earlier versions. Owners and co-authors can restore a version and save or remove milestones. History isn't on the phone layout yet; use a computer or tablet.

If you work with an AI assistant connected to Write, it can read a scene's history, mark a milestone, and (when you ask it to) restore a version. See Working with an AI.

Put a full-page picture or a spread in a scene

This page is for giving a picture whole pages in the middle of a scene: a full-page illustration, or one wide picture across two facing pages. The words around it stay where they are. In print the text fills the page it's on, the picture comes next, and the text picks up again after it, the way an illustrated novel does it.

Add one

  1. Click in the scene where the picture belongs, between two paragraphs.
  2. Insert an image the usual way, and choose your picture.
  3. Under Placement, choose Full Page Next or Two-Page Spread.
  4. Click Insert.

Screenshot: the Insert an image window with Full Page Next and Two-Page Spread Screenshot: the Placement card in the Insert an image window, with the second row (Full Page Next, Two-Page Spread) and the note under it.

In the editor's page view the picture takes no room in your text, because in print it doesn't either. You'll see a small thumbnail in the margin beside the spot, tagged Full page or Spread. Click it to change or remove the picture. To see the pages as they'll print, open Preview.

A full page

The picture gets a page to itself: the next page after the one your text is on when it reaches that spot. The page has no running head or page number, like any illustration plate. Tick Runs to the edge for a picture that bleeds off the sheet; leave it off to keep it inside the margins.

A two-page spread

Upload the whole picture once, as wide as you like. Write cuts it down the middle, so the left half sits on a left-hand page and the right half on the right-hand page facing it. A spread always runs to the edges.

A spread has to start on a left-hand page, or the halves won't face each other. When the text reaches your picture with a right-hand page coming next, Write lets the text carry on through that page first, so the spread may sit a page later than the spot you chose. You'll never get a blank page out of it, except in the rare case of a single paragraph longer than a whole page.

Keep faces and words away from the middle of a spread picture. The binding swallows a little of it.

In the ebook

An ebook has no pages to give, so a full page or a spread shows where it sits, the whole picture at the width of the screen, with its caption if it has one. In print the caption isn't used.

If an AI is adding the picture

Through Write's connector, an AI writes the same thing as ![caption](image:<id> page) or ![caption](image:<id> spread). See How an AI writes formatting into your scenes.