How Frontends Talk to a Database

• Code in the browser is visible to anyone. Database credentials in frontend code would be exposed.
• Browsers can't speak database protocols anyway; they speak HTTP.
• The backend (e.g. Node/Express, Go/Echo) validates requests, applies business rules, and talks to the database. The frontend only calls its endpoints.
• Where the request code lives differs by framework. In React, it's common to fetch directly inside a component (in useEffect), optionally extracted into an API module or custom hook. In Angular, HTTP calls are typically placed in an injectable service; components inject the service and never touch HttpClient or URLs directly. Every Angular example in this chapter follows that convention.

React / Angular app  ──HTTP──▶  Backend API  ──▶  Database       (browser)        JSON       (server)