Introducing Google Tag Manager
The basic Google Analytics code (see Chapter 2) isn’t very complicated. Put it in your template and you’re all set. Except… Well, there are still a bunch of chapters left in this book with additional types of data you might want to track with GA, many of which involve adding more code. A little piece here for PDF tracking, another little bit over there to track user logins, and so on. The more code you add, the harder it becomes to keep track of all the little pieces, and which of those pieces should be included and under what circumstances, and what happens when you make a change.