# Concepts and definitions
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For a general reference of AWS terms, see the [AWS glossary](https://docs.aws.amazon.com/general/latest/gr/glos-chap.html) in the AWS General Reference.

 **segment** 

Apache Druid stores its data and indexes in *segment files* partitioned by time. Druid creates a segment for each segment interval that contains data.

 **quorum** 

A replicated group of servers in the same application is called a *quorum*, and in replicated mode, all servers in the quorum have copies of the same configuration file.

**Note**  
For a general reference of standard Apache Druid concepts, refer to the [Apache Druid documentation](https://druid.apache.org/docs/latest/design/).