Difference between http.get and http.request

Try:

  var options = {
    host: 'example.com',
    path: '/',
    method: 'GET'
  };
  http.request(options, callback).end();

I think the issue is that the path isn't specified, so it's asking the server for a page called "", which it complains about.

If you used var options = url.parse('http://example.com') it'd neatly populate everything you need for you.

Why do I get different responses when using 'get' and 'GET'?

Because that string is being sent to the HTTP server as-is, and the HTTP server is case-sensitive. Espruino doesn't convert it to upper-case for you just in case you're trying to do something non-standard with an HTTP server.

I'll add something to the docs on it.