What are the two types of branching in a story?

The two types of branching usually described are open branching, where each choice leads to a permanently separate path, and foldback (or merging) branching, where paths split and then rejoin at key moments. Open branching gives the most freedom but multiplies the writing fast, since every choice doubles the content ahead. Foldback branching is the practical workhorse: you let readers make meaningful choices, then guide the branches back to shared scenes so the story stays manageable. Most real interactive stories mix both, branching wide at big moments and folding back elsewhere. Designers sometimes name specific shapes like the time cave, gauntlet, or branch-and-bottleneck, but they all come down to how much paths diverge versus reconnect. You can see the shape clearly by laying it out in a node graph.