Error "Unknown file extension ".ts"" when running TypeScript in Node.js

Hi! I'm new to TypeScript and trying to run my first project. I installed Node.js, created a file `index.ts` with simple code: ```typescript const greet = (name: string): string => { return `Hello, ${name}!`; }; console.log(greet("World")); ``` I'm trying to run it via `node index.ts`, but I get the error: `TypeError [ERR_UNKNOWN_FILE_EXTENSION]: Unknown file extension ".ts" for C:\\projects\\test\\index.ts` I already installed TypeScript globally via `npm install -g typescript`, but that didn't help. I also tried installing `ts-node` — the error remains. My `package.json` looks like this: ```json { "name": "test-project", "version": "1.0.0", "type": "module" } ``` Tell me, what am I doing wrong? How do I properly set up the project to run TypeScript?