# Preface

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**This is the manual for older MicroStream versions (Version < 5.0).**

**The new documentation (Version >= 5.0) is located at:**

[https://docs.microstream.one/](https://docs.microstream.one/manual)
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Welcome to the MicroStream Reference Manual. This manual includes concepts, instructions and examples to guide you on how to use MicroStream [Data-Store](https://manual.docs.microstream.one/data-store/overview) and [Cache](https://manual.docs.microstream.one/cache/overview), version 4.1.

You should be familiar with the Java programming language and you should have installed your preferred Integrated Development Environment (IDE). But since you are here we guest you got that covered ;)

## What's new in 4.1

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[changelog](https://manual.docs.microstream.one/changelog)
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## API Docs

The API documentation is available at <https://api.docs.microstream.one/>.

## Support

For information on the commercial support for MicroStream see [microstream.one](https://microstream.one/support).

## License

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[license](https://manual.docs.microstream.one/license)
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