What is routing?

Routing refers to determining how an application responds to a client request to a particular endpoint, which is a URI (or path) and a specific HTTP request method (GET, POST, and so on).

Route definition takes the following structure:

Where:

1
app is an instance of express.
2
METHOD is an HTTP request method, in lowercase.
3
PATH is a path on the server.
4
HANDLER is the function executed when the route is matched.