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Android uses a concept called content providers for abstracting data into services. This idea of content providers makes data sources look like REST-enabled data providers, such as web sites. In that sense, a content provider is a wrapper around data. A SQLite database on an Android device is an example of a data source that you can encapsulate into a content provider.
NOTE: REST stands for REpresentational State Transfer. When you type a URL in a web browser and the web server responds with HTML, you have essentially performed a REST-based “query” operation on the web server. REST is also usually contrasted with (SOAP—Simple Object Access Protocol) web services. You can read more about REST at the following Wikipedia entry: http://en.wikipedia.org/wiki/Representational_State_Transfer.