Beside chrome flutter has web server build type, What is it and if it's like chrome, whats their difference?

Beside chrome flutter has web server build type, What is it and if it's like chrome, whats their difference?

Chrome launches the application using the development compiler in a Chrome browser.
A release (web server) build uses dart2js (instead of the development compiler) to produce a single JavaScript file main.dart.js. You can create a release build using release mode (flutter run --release) or by using flutter build web. This populates a build/web directory with built files, including an assets directory, which need to be served together.
From the manual https://flutter.dev/docs/get-started/web