> ## Documentation Index > Fetch the complete documentation index at: https://shapesinc-4644c49f-cursor-docs-product-refresh-1067.mintlify.site/llms.txt > Use this file to discover all available pages before exploring further. # Glossary > Every Shapes term in one place: Shape, engine, preset, Free Will, memory, skills, credits, and the rest. Look up a word and get back to building. The words you'll see around Shapes, in plain English. New here? Start with [How Shapes Works](/core-concepts) to see how it all fits together. **Activation.** Turning a Shape on so it replies to every message in a chat, no @mention needed. You can activate up to five Shapes per chat. Use the Participants menu or `/activate`. See [Chats 101](/chats-101). **Branch off.** Splitting a conversation off from any message to try a different direction, while keeping the original. See [Branch Off](/branch-off). **Chat.** A space where people and Shapes talk together. It can hold people, Shapes, or both. Sometimes called a chat. See [AI Group Chats](/ai-group-chats). **Creator Dashboard.** Where you set up a Shape: personality, knowledge, memory, engine, voice, and more. It's at [shapes.inc/dashboard](https://shapes.inc/dashboard). See the [Shape Settings Reference](/shape-settings). **DM.** A one-on-one conversation with a Shape that sticks around, separate from a group chat. **Engine (model).** The AI model a Shape runs on, like Claude, GPT, or Gemini, plus 300+ others. It's the raw intelligence under the character. See [Which Model Should I Use?](/choosing-a-model). **Fallback engine.** The backup model a Shape uses if its main one is briefly unavailable. **Fandom chat.** A shared space built around a fandom, with characters and community context. See [Fandom Chats](/fandomchat). **Fast forward (skip turn).** Getting Shape replies without typing a new message. Handy for moving a scene along. See [Multiple Messages](/multimessages). **Free engine.** A model that costs no [Shape Credits](/credits). A strong free one is always available. **Free Will.** The per-chat settings that decide when a Shape speaks on its own: reply when mentioned, keep the convo going, react to keywords, always have something to say, and come back later. It's the heart of [social intelligence](/designing-social-intelligence). **Group chat.** A chat with several people and Shapes sharing one conversation. The core of multiplayer AI. **Initial message.** What a Shape says when a conversation first starts. See [Initial Messages](/initialmessages). **Knowledge.** A bank of facts you give a Shape (lore, custom command responses, relationships), pulled in by relevance during chat. Keep it lean. See [Designing Great Shapes](/designing-shapes). **Long-term memory (LTM).** Lasting memories a Shape keeps about people and events, recalled across different conversations. See the [Memory Guide](/memory). **MCP (Model Context Protocol).** A standard for plugging custom tools into a Shape, through providers like Smithery. See [Shape Skills](/shapeskills). **Multiplayer AI.** AI that lives inside a shared conversation with other people. The whole idea behind Shapes. See [What Is Multiplayer AI?](/articles/what-is-multiplayer-ai). **Persona.** How a Shape sees you: the name to call you and what to remember about you. It lets a Shape treat different people differently. See [Personas](/personas). **Premium engine.** A top-tier model that costs [Shape Credits](/credits). Buy credits or earn them free through [rewards](/rewards). **Preset.** The instructions that control *how* a Shape writes (length, format, voice), separate from who it is. It uses the `{shape}` and `{user}` variables. See [Presets](/presets). **Regenerate.** Asking a Shape for a fresh version of a message. See [Regeneration](/regeneration). **Shape.** An AI character you can talk to or build, with a personality, memory, voice, and a role in the conversation. See [What's a Shape?](/what-are-shapes). **Shape Credits.** The currency for premium engines and some premium features. Buy them or earn them free. See the [Credits Guide](/credits-guide). **Shape Skills.** Tools that let a Shape *do* things beyond talking: web search, code, image generation, custom integrations, and more. See [Shape Skills](/shapeskills). **Short-term memory (STM).** The recent messages in the chat you're in that a Shape reads as it replies. **Social intelligence.** The craft of a Shape knowing when to speak and when to stay quiet in a group. See [Designing Social Intelligence](/designing-social-intelligence). **Sponsored chat.** A chat where premium engine use is covered, so everyone gets premium for free. See the [Credits Guide](/credits-guide). **Time awareness.** A setting that lets a Shape know when messages were sent and how much time has passed. **Training.** Example input/output pairs that guide a Shape's style. It learns the pattern instead of repeating the examples word for word. **Vanity URL.** A Shape's custom username and link. See [Vanity URL](/vanityurl). **Vision.** A model's ability to understand images you send. Look for the **Native Vision** badge on the [engines page](https://shapes.inc/engines). **Voice call.** A live, spoken conversation with a Shape. Experimental and free. See [Voice Calls](/voicecalls). **Voice message.** An audio reply from a Shape in its own voice, with an optional text transcript. See [Give Your Shape a Voice](/how-to-give-your-shape-a-voice). **`/wack`, `/reset`, `/sleep`.** The memory commands. `/wack` clears short-term memory, `/reset` erases long-term memory, and `/sleep` saves the conversation to long-term memory. See the [Commands Reference](/commands). [Back to the docs](/introduction)