Fwiw a branch isn't a named sequence of commits, it's just a label that points to a single commit. It's exactly the same as a tag except that git moves it when you make a new commit.

Mercurial calls these bookmarks which IMO is a much better name because it works exactly like real bookmarks (in books, not browsers). A git branch feels a little bit like a branch of a tree because each commit points to their parent. Therefore, you don't need to track the entire sequence of commits in the branch but just the commit at the tip. I think if they'd had named only this concept better, Git would've been way easier to grok.

I wouldn't usually nitpick like this but given that the entire point of this article is it matters to get the basic concepts right, I figured the author might want to get this basic concept right.