Roll Up vs. Website

The roll-ups combine different websites. I find the features of Roll-Ups here:
What can I not do with roll-ups, what can I do with websites?

It is used to show the performance of many pages aggregate at a glance.
I think the documentation explaines it very well.

Let’s say you have Website A and B
Both are exactly the same except eg. the language.
If both sites have the same tracking and Ecommerce events implemented you would be able to see the overall performance in one dashboard.


thank you for the answer. In the rough concept I have already understood this. It would just be interesting to know what a roll-up cannot depict. E.g. a user who switches from website A to B will be displayed twice or that it is not possible to define targets. Are there any other peculiarities you should be watching out for?



Switching between sites will produce two visits, they will not merge. To have the visits appear in one visit you would want to use cross-domain tracking: