What does `app.use(bodyParser.json())` do?

Question

For:

bodyParser.urlencoded({extended: ...})

my research shows me that if extended: true, then you can parse nested objects, or

Answer 1

bodyParser.json returns middleware that only parses json. This parser accepts any Unicode encoding of the body and supports automatic inflation of gzip and deflate encodings.

A new body object containing the parsed data is populated on the request object after the middleware (i.e. req.body).