What is npm and what is package.json in a JavaScript project?

npm is a package manager and registry ecosystem for JavaScript. In a project, package.json lists dependencies, devDependencies, and scripts. node_modules is where installed packages go (and can get large), and lockfiles (package-lock.json with npm) help pin exact versions for reproducible installs. You still need to understand security: dependencies are part of your supply chain.

{
  "name": "talvior-web",
  "scripts": { "dev": "next dev" },
  "dependencies": { "next": "16.2.3" }
}

Start simple: try this concept in a tiny project before moving to advanced tools.