Deferred wrapper of cherio request

deferredRequest.js

var deferred = require('deferred'),
    request = require('request'),
    cheerio = require('cheerio');

var deferredRequest = function(url) {
    var d = deferred();

    request(url, function (err, resp, body) {
        if(err) {
            d.reject(new Error("Unable to fetch '" + url + "', reason: " + err));
            return;
        }

        if(resp.statusCode !== 200) {
            d.reject(new Error("Unable to fetch '" + url + "', code: " + resp.statusCode));
            return;
        }

        d.resolve(body);    
    });

    return d.promise();
};

////////////////////
// Example usage
////////////////////

// Load URL
deferredRequest("http://www.firmy.cz/a").then(function(data) {
    // THIS BLOCK IS DEFERRED HANDLER OF HTML DATA

    // Load HTML to cheerio
    var $ = cheerio.load(data);

    // Prepare results array
    var result = [];

    // Iterate all resultsl
    $('ul.abc > li > a').each(function (element) {

        // Push them to result array
        result.push({
            href: this.attr("href"),
            text: this.text()
        });
    });

    // Create immediately resolved promise and resolve it with result
    return deferred(result);

}).done(function(res) {
    // THIS BLOCK IS NEXT HANDLER (see previous block)

    console.log(JSON.stringify(res, null, 4));
}, function(err) {
    console.log("ERROR: " + err);
});

What's the difference between using defer or using Promises directly?

For example:

function scrapp (data) {
  const $ = cheerio.load(data)
  let promises = []
  return new Promise((resolve, reject) => {
    $('a').each((i, el) => {
      const text = el.attribs.title
      const href = el.attribs.href
      promises.push({text, href})
    })
  resolve(promises)
  })
}