In vPlan you will encounter the term card, but also the term collection. What is the difference between these two?

A collection is a group of cards that belong together. It also contains overarching information that is shown on each linked card, such as the title, description, custom fields, comments and followers. A collection always has at least one card, and conversely a card always has one collection (1 to 1 relationship), but a collection can also consist of multiple cards (1 to more relationship). Each card that belongs to a collection has its own status, activity and labels.

When you create a card in the backlog, it is actually always a collection in which you enter a title, description, activities and possibly labels. If you plan the collection from the backlog, the collection is divided into one or more cards. This is the case when you work with multiple stages in your board, or when you split a collection into multiple cards after planning.

Within a collection you can plan and move the cards individually, but you can also move them as an entire collection. You can read how this works in chapter Select collection in this article: Basic plan functionalities