Scopes are a way of grouping related packages together, and also affect a few things about the way npm treats the package.
Each npm user/organization has their own scope, and only you can add packages in your scope. This means you don't have to worry about someone taking your package name ahead of you. Thus it is also a good way to signal official packages for organizations.
Scoped packages can be published and installed as of
npm@2 and are supported by the primary npm registry. Unscoped packages can depend on scoped packages and vice versa. The npm client is backwards-compatible with unscoped registries, so it can be used to work with scoped and unscoped registries at the same time.
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