I want to understand how Adobe Target reads the digital data layer. From one of my experiences, I was trying to pass page title from a data layer
While I used reading via javascript variable it did not work for me:
![jsvasu_0-1696270205580.png jsvasu_0-1696270205580.png](https://experienceleaguecommunities.adobe.com/t5/image/serverpage/image-id/64043i1DE383CD579E1042/image-dimensions/827x282?v=v2)
However, reading it as a core attribute worked
![jsvasu_1-1696270252466.png jsvasu_1-1696270252466.png](https://experienceleaguecommunities.adobe.com/t5/image/serverpage/image-id/64044i734437A49BC338D8/image-dimensions/752x245?v=v2)
Why this is the case?
Also, I have pages with multi-product categories and they get passed into my data layer in the form of an array, and through JS code I am already successfully reading it via data element into eVars for my analysis. However, when I am trying to map this multi-product categories data element to user.categoryId to pass it as a Target mbox parameter for every page load nothing comes up in my favorite categories. Any suggestions as to why? This is why I am wondering how to read values out of the digital data layer into data elements for Target?
![jsvasu_2-1696270460683.png jsvasu_2-1696270460683.png](https://experienceleaguecommunities.adobe.com/t5/image/serverpage/image-id/64045i96D75F6BAE10107A/image-dimensions/786x55?v=v2)