Google Data Layer
Google Data Layer allows us to push extra metadata through to Google Tag Manager, giving you more granular insights to really understand web behaviors.
Data layer is an object that carries all the information that you want to pass from a website to other applications. Data layer ensures flexibility, portability and ease of implementation.
Properly constructed data layers are one of the most crucial aspects of an efficient Google Tag Manager setup, and unfortunately one of the most misunderstood aspects of it.