title: Client fetch a request to a node js file on the server
body: <p>I've coded an API that runs on my server (that could be myserver.com) using node.js, this js file is listening on port 3000 using express.</p>
  <p>Now I would like that the file &quot;main.js&quot;, that it's running in client browser, send a data to the node file on the server, and that it will send a response to the client.</p>
  <p>I'm getting in trouble with the routing. I do not understand which url I've to fetch to.</p>
  <p>Thank you!</p>