Forking takes a copy of a card from a remote site into the Origin site. This action preserves a snapshot of the card at that point in time. That snapshot may or may not be different from the current content of the card on the remote site, that can evolve independently.
The *Fork This Card* button [ ⚑ ] appears at the bottom of every card. It is one of two special buttons tucked into the lower right corner of the the Journal.
Find the fork button [⚑] at the bottom of every page to the right of the journal.
When the copy is complete, a fork action is recorded in the new page's journal. The fork action appears as a black flag icon over the remote site's gradient flag background.
You can click the fork action in your journal to recall the remote page at any time.
The term *fork* is commonly used in the development of open source software. It enables an individual to take a copy of part of a collaborative work under personal control, while others in the community or team proceed in parallel. If changes on each fork are independent of each other, it's easy to Merge Changes together.
The alternative to the *fork, then merge* protocol is to *check-out, then check in* that is familiar to anyone who has ever taken a book out of a public library. In the physical world, only one person can make changes to a tangible work at any time (leading to the mess of photocopying). With electronic media, perfect copies can be made available to multiple editors simultaneously.