Built on VS Code, Cursor adds AI that understands your entire codebase. Ask it to 'add authentication to this app' and it writes the code across multiple files. It can explain confusing code, fix bugs, and refactor functions. Free tier includes limited AI requests. Pro ($20/month) adds GPT-4 and unlimited usage. It's rapidly becoming the default editor for AI-assisted coding.
**Key takeaway:** Cursor = VS Code with AI that understands your whole codebase.