Google analytics - difference between ga.js and analytics.js

Question

Working on "Google Analytics", Track our website using ga.js and also analytics.js but I don't know the difference between them. Is there any difference in them except the syntax! :D

(function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){
      (i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o),
      m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m)
      })(window,document,'script','//www.google-analytics.com/analytics.js','ga');

And when I created an account(Google Analytics) it just gave me the tracking code by analytics.js why not ga.js. Is analytics.js is the one recommended by them or what!

Answer 1

Analytics.js is the new universal analytics profile. You set classic or universal when you create the profile. You are not able to switch a profile between classic and universal, instead you need to create a new profile to switch between profile types.

Answer 2

analytics.js is the new standard. All new functionality will be added to the code. The classic implementation will be deprecated and data collected for 2 years only.

Currently you only have classic implementation if you have done it before because Google will only give you the new code.