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<head>
  <title>Tutorial - Application Property Store</title>
</head>

## [Helix Tutorial](./Tutorial.html): Application Property Store

In this chapter, we\'ll learn how to use the application property store.

### Property Store

It is common that an application needs support for distributed, shared data structures.  Helix uses ZooKeeper to store the application data and hence provides notifications when the data changes.

While you could use ZooKeeper directly, Helix supports caching the data with a write-through cache. This is far more efficient than reading from ZooKeeper for every access.

See [HelixManager.getHelixPropertyStore](http://helix.apache.org/javadocs/1.4.2/reference/org/apache/helix/store/package-summary.html) for details.
