What is emmet?

Emmet is a shorthand system for web developers that lets you write short codes and expand them into full HTML or CSS automatically. Instead of typing out every tag and attribute by hand, you type a brief expression and Emmet converts it into complete, properly nested code. Most popular code editors already bundle Emmet or offer it as a plugin, so many developers use it without knowing what is running underneath. The shorthand syntax borrows from CSS selectors, which are the patterns web developers already use to describe page elements. For example, typing a short expression like ul#nav>li.item$*4>a{Item $} and pressing a key produces a four-item navigation list with correctly named IDs, classes, and link text. The same idea applies to CSS properties: short codes expand to full property declarations, including units and color values. Beyond HTML, Emmet supports several other template and stylesheet formats, including JSX (used with React), HAML, Pug, SCSS, and Sass. You can also point it at a custom syntax and configure exactly how the expanded output should be formatted. This particular repository is the core engine that handles parsing and expanding abbreviations. It does not include any editor plugin code. Editor-specific plugins live in separate repositories under the same organization and call into this core library. The repository is structured as a monorepo: the root contains the main expansion logic, and a packages folder holds standalone parsers that can be used independently, for example as a syntax highlighter. Installing the core library requires npm, the standard JavaScript package manager. Once installed, a single function call takes an abbreviation string and returns the expanded code. Developers building editor plugins or custom tooling would use this library directly, most end users interact with Emmet through an editor extension instead.