I have pasted the following code in the <head> section of all of my pages to connect to Google Analytics:
<!-- Global site tag (gtag.js) - Google Analytics -->
<script async src="https://www.googletagmanager.com/gtag/js?id=UA-*********-*"></script>
<!-- Google Analytics -->
<script>
window.dataLayer = window.dataLayer || [];
function gtag() { dataLayer.push(arguments); }
gtag('js', new Date());
gtag('config', 'UA-*********-*');
</script>
<!-- End Google Analytics -->
I have seen this article which talks about upgrading from Analytics.js to gtag.jas. I believe I am already using the new version so I believe I don't need to do any updates...
At the same time, I have created a Google Tag Manager account and created a Tag for my Google Analytics. The Tag Manager asks me to add the following code to my <head> and <body>
<!-- Google Tag Manager -->
<script>
(function (w, d, s, l, i) {
w[l] = w[l] || []; w[l].push({
'gtm.start':
new Date().getTime(), event: 'gtm.js'
}); var f = d.getElementsByTagName(s)[0],
j = d.createElement(s), dl = l != 'dataLayer' ? '&l=' + l : ''; j.async = true; j.src =
'https://www.googletagmanager.com/gtm.js?id=' + i + dl; f.parentNode.insertBefore(j, f);
})(window, document, 'script', 'dataLayer', 'G**-*******');</script>
<!-- End Google Tag Manager -->
<!-- Google Tag Manager (noscript) -->
<noscript>
<iframe src="https://www.googletagmanager.com/ns.html?id=G**-*******"
height="0" width="0" style="display:none;visibility:hidden"></iframe>
</noscript>
<!-- End Google Tag Manager (noscript) -->
Question
What is the difference between former and latter .js snippets? Do I need to include both of them on my page or either one would do the job?
At the moment, I am only using the former code and my Google analytics is working fine... I am just confuse what is the purpose of Tag Manager snippet and if I need to include it in my code?
