What's the difference between creating a server using http module and creating a server using express framework in node js? Thanks.
Ultimately, express uses node's http api behind the scenes.
The express framework provides an abstraction layer above the vanilla http module to make handling web traffic and APIs a little easier. There's also tons of middleware available for express (and express-like) frameworks to complete common tasks such as: CORS, XSRF, POST parsing, cookies etc.
The http api is very simple and is used to to setup and manage incoming/outgoing ,HTTP connections. Node does most of the heavy lifting here but it does provide things you'll commonly see throughout most node web framework such as: request
/response
objects etc.