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Chapter 15
Useful Packages

DrScheme users have contributed numerous useful packages, which you can find at the following repository:

`http://planet.plt-scheme.org/`

In addition, individual developers and textbook authors also disseminate packages.

Most of these packages are in the `.plt` format. This is a cross-platform, self-installing format specific to DrScheme. To install a `.plt` file, whether on the Web or on the local filesystem, use File | Install .plt File....