BEGINNER

Claude Code skills are SKILL.md playbooks that load only when relevant. What they are, where they live, how to write one, and how they differ from CLAUDE.md.

An AI coding agent takes a task, uses tools like editors and shells, and loops until done. The five kinds, the top agents compared, and what they get wrong.

Cursor is a VS Code fork with AI at its center. What Tab, inline edit, agent chat and Cloud Agents do, and how it compares to Copilot and Claude Code.

Claude Code is Anthropic's AI coding agent for terminal, IDE, desktop and browser. What it does, how it works, setup, pricing, MCP, skills, hooks and subagents.