Appendix E: Glossary#

Agent — An AI system that can take actions, not just generate text. Claude Code is an agent because it can read files, run programs, and interact with your computer.

CLI (Command Line Interface) — A text-based way to interact with software. Claude Code is a CLI tool — you interact with it by typing text in a terminal.

CLAUDE.md — A markdown file that Claude Code reads automatically at session start. It serves as persistent project memory, containing instructions, context, and decisions that Claude should know about.

Context window — The amount of information Claude can hold in a single conversation. When you approach the limit, use /compact to compress the conversation.

ffmpeg — An open-source tool for processing video and audio files. Claude uses it for converting formats, burning subtitles, extracting audio, creating GIFs, and more.

Git — A version control system that tracks changes to files over time. Think of it as an unlimited “undo” history for your project. Claude uses it to save your work and deploy websites.

GitHub — A website that hosts Git repositories (project folders with version history). Claude uses it as the bridge between your local project and web hosting.

GitHub CLI (gh) — A command-line tool for interacting with GitHub. Claude uses it to create repositories, push code, and manage projects.

Hook — An automated action that runs at a specific moment in Claude Code’s lifecycle (e.g., when a session starts). Configured in your settings file.

JSON — JavaScript Object Notation. A text format for storing structured data. Claude Code’s settings files (settings.json) use this format. You rarely need to edit these manually.

Markdown — A simple text formatting language that uses symbols like # for headers and ** for bold. CLAUDE.md files and many of Claude’s outputs use markdown.

MCP (Model Context Protocol) — A system for connecting Claude Code to external tools and services. MCPs give Claude new capabilities (like browser automation or data API access).

Model tiers (Sonnet, Opus, Haiku, Fable) — Anthropic ships its models in capability tiers. As of mid-2026: Sonnet 5 is the Pro plan default (1-million-token context window, thinking on by default), Opus 5 is the smartest everyday tier (default on Max and Team Premium), Haiku is the fast and affordable tier, and Fable 5 is the most capable model, available on the API and cloud platforms rather than as a subscription default. Type /model to see and switch yours.

Node.js — A program that lets JavaScript run on your computer. Required for installing Claude Code.

npm — Node Package Manager. The tool used to install Claude Code and other Node.js-based tools. npm install -g @anthropic-ai/claude-code installs Claude Code.

Permission — Claude Code’s safety system. Before taking certain actions, Claude asks for your approval. Permissions can be pre-approved in settings.local.json.

Plan Mode — A Claude Code mode where Claude can research and plan but cannot make changes to your files. Activated with Shift+Tab or --permission-mode plan.

Plugin — An add-on package that extends Claude Code’s capabilities with specialized skills, commands, agents, or hooks.

RTF (Rich Text Format) — A document format that preserves formatting (bold, italics, bullets) when pasted into other applications. Preferred over markdown for LinkedIn content.

Skill — A SKILL.md file with YAML frontmatter that teaches Claude how to handle a specific type of task. Skills can live standalone in ~/.claude/skills/ (personal, across all projects) or .claude/skills/ (a single project), or they can be bundled inside a plugin. Claude activates a skill automatically when the task matches its description, or you can invoke one directly with /skill-name (for standalone skills) or via the parent plugin’s commands (for plugin-bundled skills).

Terminal — The text-based interface on your computer where you type commands. On Mac, it is called “Terminal.” Claude Code runs inside the terminal.

Vercel — A free web hosting platform that automatically deploys websites from GitHub repositories. Claude uses it to put your websites on the internet.

Working directory — The folder you are currently “inside” in the terminal. Claude Code operates relative to this folder — it is the context for all file operations.

Whisper — OpenAI’s open-source speech-to-text model. Claude uses it to transcribe audio and video files locally on your machine.

yt-dlp — An open-source tool for downloading videos from YouTube and other platforms. Claude uses it for all video downloading tasks.