This project is a sample WebPart were there are two different methods of getting list items (one classic approach and one with caching). The caching method is fasts and more recommended approach for bigger lists. Every other request to the same resources from list are first checked if are present in cache and if yes then it is taken from it first. Also in the WebPart we may find some examples to get user profile properties, permissions and groups.
The last thing that is present is saving data to ULS and developer dashboard. This are very important methods of logging that should be used during development (developer dashboard) and should be always present in production stage of any application (logging to ULS) in order to save unexpected errors
MSDN resource helpful to understand the used technology
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