Data layer basics

What is the data layer?

The data layer is the foundation of tag management. The data layer defines attributes about your website, such as site language or page name, as well as important user behaviors that you want to track, such as purchases and logins. Defining the attributes of your data layer is the first step in implementing tag management. Adding a data layer to your website page code is the primary development effort required for tag management.

How it works

Before we add your first data layer variable, let’s review how it works:

• JavaScript object
  Most data layer variables created in is also added to your page code in a JavaScript object named utag_data, also known as the Universal Data Object (UDO).
• Consistent names
  The data layer variable names defined in TiQ must match the names of the variables populated in your page code. For example, a data layer variable named page_name in is populated in your page code as:

  utag_data = { "page_name" : "My Home Page" };
  

• User-friendly variable names
  Data layer variables have user-friendly names that are vendor-neutral and easy to understand across all of your business units, for example order_id instead of oid.
• Additional page data
  In addition to the variables you define, the data layer also makes use of the following data from your web pages: meta data tags, URL components, query string parameters, cookies, local and session storage, and other global JavaScript variables.