What is API ?

API is the acronym for Application Programming Interface, which is a software intermediary that allows two applications to talk to each other. Each time you use an app like Facebook, send an instant message, or check the weather on your phone, you’re using an API.

REST APIs

Web services were originally designed to communicate using SOAP (Simple Object Access Protocol), a messaging protocol that sends XML documents over HTTP. Today, however, most web-based APIs use REST—Representational State Transfer—as an architectural style. The response is sent in the form of JSON.

One of the big differentiators of REST is that it involves sending data to the requesting application. While this provides great flexibility, allowing the application to do whatever it wants with the data, it comes at the cost of efficiency. Sending data over the web for processing is quite slow compared to doing the processing where the data resides and then sending the results.

How to make sample API call

Given below is a snippet showing a sample API request. I tried my best to add some most used languages in the below example.

      
  var https = require('follow-redirects').https;
  var fs = require('fs');

  var options = {
  'method': 'GET',
  'hostname': 'api.twitter.com',
  'path': '/2/tweets/20',
  'headers': {
  },
  'maxRedirects': 20
  };

  var req = https.request(options, function (res) {
    var chunks = [];

  res.on("data", function (chunk) {
    chunks.push(chunk);
  });

  res.on("end", function (chunk) {
    var body = Buffer.concat(chunks);
    console.log(body.toString());
  });

  res.on("error", function (error) {
    console.error(error);
  });
});

req.end();