GTM Definition

What is GTM (Google Tag Manager)? 

 GTM is a tag management solution which acts as an intermediary between a website and 3rd party tracking tools. You need to add the tracking codes to GTM and then configure the rules when they should fire. 

 Why using it? 

 1) With GTM we can test the tags to make sure they are triggered when we load a page or click a particular button. 2) We can change the tags without changing the website's source code. 3) GTM lets us manage various JavaScript tracking codes on a website. 4) Fast Deployment of Tracking Codes 5) All Tags in one place 6) Testing and debug tools 7) Tag templates > you don't have to setup everything from scratch 8) HUGE active community on FB 9) Versions of the container (you can restore everything) 10) Dynamic Tagging + Privacy Policies 

 How it works? 

 A tag is a piece of code that fires on a website under certain circumstances. It can be a tracking code, some piece of code that changes the text or a particular website element, or even a code which changes the color of the browser's address bar, etc. When you create a tag, you basically instruct Google Tag Manager to "do this", "do that", "track page views of this visitor", "track this click and send to Google Analytics" etc. A trigger is a condition when a tag must fire. Should a tag fire on all page views? Or maybe on certain clicks? How about successful form submissions? All these examples are triggers. When a particular condition (or a set of conditions) is met, a trigger is activated and all the tags (linked to it) are dispatched. A variable is the final member of this trinity. Variables are little helpers that can be used in tags, triggers, or even in other variables. A variable can: ▪ Hold a single piece of data (like page URL, website domain, product ID, text of a link, etc.) ▪ Hold a set of data/settings (Universal Analytics Google Analytics settings variable contains multiple settings related to GA, like Tracking ID, Display Advertising settings, etc.)