## Using Atmosphere packages
### When to use Atmosphere packages

Atmosphere packages are packages written specifically for Meteor and have several advantages over npm when used with Meteor. In particular, Atmosphere packages can:

- Depend on core Meteor packages, such as `ddp`, `mongo` or `accounts`
- Explicitly include non-javascript files including CSS, Less or static assets
- Have a well defined way to ship different code for client and server, enabling different behavior in each context
- Get direct access to Meteor's [package namespacing](#atmosphere-package-namespacing) and package global exports without having to explicitly use ES2015 `import`
- Enforce exact version dependencies between packages using Meteor's [constraint resolver](#semantic-versionning-and-version-constraints)
- Include [build plugins](https://docs.meteor.com/api/package.html#build-plugin-api) for Meteor's build system
- Include pre-built binary code for different server architectures, such as Linux or Windows

If your package depends on another Atmosphere package, or needs to take advantage of Meteor's [build system](https://docs.meteor.com/about/modern-build-stack.html#modern-build-stack), writing an Atmosphere package might be the best option for now.
