Prettier is an opinionated code formatter that supports JavaScript, TypeScript, JSX, CSS, SCSS, Less, HTML, JSON, Markdown, YAML, GraphQL and a growing list of languages through plugins. Instead of tweaking dozens of style rules, a team installs it once and lets it parse source files into an abstract syntax tree and reprint them in a single canonical layout.
The official site documents installation, the command line interface, configuration through .prettierrc and .prettierignore, editor integrations for VS Code, JetBrains and Vim, pre-commit hooks, and the playground where you can paste code and immediately see how each option changes the output. A rationale page explains why the option set is deliberately small.
It suits frontend and backend teams that want consistent diffs in pull requests, open-source maintainers who receive patches from many contributors, educators teaching a uniform style, and continuous integration pipelines that need a fast, deterministic check before code is merged.
Compared with configurable linters it focuses purely on layout rather than code quality, so the two are commonly used together; compared with editor-native formatters it behaves identically on every machine and in every CI job, though its fixed choices can be frustrating for teams with strong house conventions.
Add a format script and a pre-commit hook early so formatting happens before review, commit the configuration file so every contributor shares it, and run Prettier once across the whole repository in a dedicated commit to avoid mixing formatting noise with functional changes.