It allows you to link cards together is the simplest way to put it. If you have cards on separate boards that are related you can connect them. Here is some great information about related cards and examples of how to use it: https://blog.trello.com/related-cards-related-boards
Thank you for the reply.
Well, I'm gathering that leaving the cards unrelated means that only the one that had the attachment sees a connection to the other. By relating them, they both point to each other, but only insofar as the attachment is loaded...
Basically it's a helpful reference, but there is no deeper relationship between the two.
Is that correct?
Hello friends! From the community that brought you Welcome Wednesday, Throwback Thursday and Friday Fun, welcome to Taco Tuesday, a weekly discussion about all things Trello. The best part? One Tac...
Connect with like-minded Atlassian users at free events near you!Find an event
Connect with like-minded Atlassian users at free events near you!
Unfortunately there are no Community Events near you at the moment.Host an event
You're one step closer to meeting fellow Atlassian users at your local event. Learn more about Community Events