# Stacks > Drop a sticky or a card onto another to stack them, named from what's in them. Group a whole selection into themes at once. Theming a planning session or a retro rarely starts with sections. People put stickies that go together on top of each other, then sort the stacks out after. A **stack** is that: stickies, issues and pull requests gathered into one theme, with a name and a count, like app folders on a phone. ![A section of stickies about what unpic 5.0 should fix, and three stacks beside it: Big sites are slow, Newcomer onboarding and Thin release notes, each with its count and its first few stickies, issues and pull requests a line each.](https://tack.social/_astro/stacks-light.DDaJF-15_1HqD5L.webp) Three stacks, named from what's in them; the ✨ marks a suggested name. ## Making a stack Drag a sticky or a card onto another and hold it there for a moment: the one underneath opens up to take it in. Let go and they’re a stack, where the one underneath was. Moving on before it opens is just a move. - **Add to a stack** the same way: drag a sticky or card (or several, or another stack) onto it and hold. - **Stack a selection** of stickies and cards with **Stack** in the selection’s action bar (`⌥` `G`): they go where the first of them is. - One undo puts everything back as it was. ## Reading and changing a stack A stack is a theme card: its name as the headline with how many it holds beside it, then its first few stickies and cards a line each (a sticky’s colour and words, a card’s state, number and title), and “+3 more” for the rest. The edges of the next ones peek out behind it, in their colours. Zoomed out, it’s just its name and count, big enough to read, so a board of stacks reads as a list of themes. - **Click it** (or select it and press `Enter`) to spread what’s in it out into a grid where it is, to read and edit it. Only you see it open: everyone else still sees a stack. Click away or press `Esc` to gather it back up. - **Drag something out** of an open stack to take it out. Drag it to another place in the grid to reorder. A stack left with one sticky or card goes back to being that. - **Unstack** in its action bar (`⌥` `U`) lays what’s in it out for good and the stack goes. - Deleting a stack deletes what’s in it with it. A stack moves as one, sits in a section like anything else, can be [dot-voted](https://tack.social/facilitation/dot-voting.md) and stamped, and connectors can join it. In a section shown as a list, it’s one row with its name and what it holds (“5 stickies”, “3 items”), and pops out as its theme card when you point at it. Exports, templates, history, copy and paste, and [board images](https://tack.social/boards/embeds.md) keep what’s in it with it. ## Names A stack is named for what’s in it, a short theme like “Hard-to-find provider docs”, marked ✨ as a suggestion. As things come and go and their text changes, the suggestion follows, a moment later. Click a stack’s name to give it one of your own, or keep the suggestion with the ✓ beside it. A name a person gave a stack is never changed by anything else; clear it to go back to suggestions. Names come from the instance’s [AI suggestions](https://tack.social/boards/stacks.md#ai-suggestions). Without them, a stack is “Untitled stack” until someone names it. ## Auto-stack Select three or more stickies, issues or pull requests and choose **Auto-stack** (`⌥` `⇧` `G`). Tack reads them and proposes stacks, each with a name. Before anything changes, you see the proposal: what goes in each stack is ringed and numbered on the board, and the panel lists it. Rename a stack, leave something out, or drop a stack, then **Make** them, in one undo step. Whatever fits no stack stays where it is. **Try again** asks for another proposal. Cards selected with the stickies stay out of it unless you tick **Include cards**: themes usually come from what people wrote. Select only issues and pull requests and they’re what’s grouped. A card whose title can’t be shared with everyone on the board (see below) is left out, and the panel says so; Tack can only group what everyone there can read. ### A whole section Select a [section](https://tack.social/boards/sections.md) on its own (an inbox too) and choose **Auto-stack** to sort what’s loose in it: its own stickies, issues and pull requests, not what’s already in a stack or in a section inside it. It works as it does for a selection, previewed the same way, and the stacks go inside the section, laid out in tidy rows where the first of what they take was, clear of whatever stays. If they need more room, the section grows to fit. Whatever fits no stack stays where it is, and it’s all one undo step. It reads up to 60 at once: in a section with more, it says so (“Auto-stacking the first 60 of 84”) and takes the first 60 in reading order. ## Making issues from a stack Select a stack and choose **Make parent issue**: its name is the parent issue’s title, and what’s in it becomes its sub-issues. Its stickies become new issues; issues already in it are linked as they are. Pull requests can’t be sub-issues, so they’re left out, and the panel says so. When the push lands, the stack spreads out and its stickies turn into their cards, with the parent’s card above them. See [Built-in actions](https://tack.social/writing-back/actions.md). ## Silent mode A face-down sticky in a [silent](https://tack.social/facilitation/silent-mode.md) section can be stacked like any other: it stays face down on the stack until the reveal, a line that says only “Face down”. Its text isn’t on the board until then, so it never lends a stack its words, and Auto-stack leaves it out. ## AI suggestions Names and Auto-stack come from a language model running on the instance’s own Cloudflare account ([Workers AI](https://tack.social/self-hosting/configuration.md#ai-suggestions)), on by default. Only stickies’ visible text is sent, and the titles of issues and pull requests that everyone who can see the board can read: a name is seen by everyone, so it mustn’t give away a title some of them can’t see. That’s a card from a public repository, or, on a board only its members can open, one every member can read. Never face-down stickies, comments or anything else. A card whose title can’t be shared still counts toward its stack, and its line on the stack shows it only to those who can read it. Each board limits how often it asks, and a stack whose text hasn’t changed is never asked about twice. An instance can turn them off.