What programming language does Twine use?

Twine does not require a programming language for basic stories, but under the hood its games are plain HTML, CSS, and JavaScript, and its story formats add their own lightweight scripting. When you build a simple branching story you only use Twine's linking syntax, with no real coding. If you want variables, logic, or custom styling, you write in the macro language of your chosen story format: Harlowe and SugarCube are the common ones, and SugarCube in particular lets you drop in JavaScript and CSS. Twine itself is built with web technologies, which is why every finished game exports as a self-contained HTML file that runs in any browser. So no language is needed to start, and web-standard scripting is available when you want more. A node-based builder takes a similar no-code-first approach.