Locations and concepts
Where things live
Where memory and Rules live (Windows and Mac)
~ means your "home directory": on Windows C:\Users\YourName\, on Mac /Users/YourName/.
| What | Windows | Mac |
|---|---|---|
| Personal global rules CLAUDE.md | C:\Users\UserName\.claude\CLAUDE.md | ~/.claude/CLAUDE.md |
| Project rules CLAUDE.md | project-folder\CLAUDE.md or project-folder\.claude\CLAUDE.md | Same (path separator is /) |
| Personal project rules not checked in | project-folder\CLAUDE.local.md | Same |
| Rules split by file type | project-folder\.claude\rules\*.md; personal, all projects: C:\Users\UserName\.claude\rules\ | .claude/rules/; personal: ~/.claude/rules/ |
| Auto memory (written by Claude itself) | C:\Users\UserName\.claude\projects\<project>\memory\ | ~/.claude/projects/<project>/memory/ |
| Rules managed by a company | C:\Program Files\ClaudeCode\CLAUDE.md | /Library/Application Support/ClaudeCode/CLAUDE.md |
Key point: CLAUDE.md is the rules you write for it; auto memory is the notes it writes for itself. Both are loaded at the start of every conversation. The auto-memory folder has a MEMORY.md index; only about the first 200 lines are read when loading, so keep the index short, one line per item. Source: official memory docs.
Skill, Command, Rule: what is the difference
| Who triggers it | When it is loaded | Where it lives | |
|---|---|---|---|
| Rule / CLAUDE.md | Automatic | At the start of every conversation | See the section above |
| Skill | The AI decides from the description, or you name it | The full text is read only when used | .claude/skills/name/SKILL.md (project) or ~/.claude/skills/ (personal) |
| Command | You type /name | When typed | .claude/commands/name.md or ~/.claude/commands/ |
Rule of thumb: must be obeyed every time → Rule; a set of steps used now and then → Skill; a fixed routine you want to trigger in one go → Command. The most important part of a Skill is the description at the top (the trigger description): say "when to use me", and the AI will remember it at the right moment. Official pages: Skills, slash commands.
A minimal Skill file:
---
name: deploy-check
description: Use after deploying a website to verify it is reachable online: curl status code, console errors, two-viewport screenshots
---
1. First curl the live URL and confirm 200
2. Open it in a browser, once at phone width and once at PC width
3. List any console errors
T00's own fixed procedure for writing Skills is also a Skill (see t00-skill-writer in the "T00 Skill list").