Q9: What is the difference between `req.params`, `req.query`, and `req.body`?
These three properties capture client inputs from different locations in an HTTP request:
req.params: Captures dynamic path segments defined in route templates (/users/:id).req.query: Captures key-value URL query parameters appended after the?symbol (/users?status=active).req.body: Captures payload data submitted in the HTTP request body (requires body parsing middleware).
Key Takeaways
- Path params reflect resource identifiers; query params reflect modifiers like page or filter.
req.bodyisundefinedby default until body-parser orexpress.json()middleware is mounted.