The Basic level gathers a limited set of information that is critical for understanding the device and its configuration including: basic device information, quality-related information, app compatibility, and Windows Store. When the level is set to Basic, it also includes the Security level information.
The Basic level helps to identify problems that can occur on a particular device hardware or software configuration. For example, it can help determine if crashes are more frequent on devices with a specific amount of memory or that are running a particular driver version. This helps Microsoft fix operating system or app problems.
Use this article to learn about diagnostic events, grouped by event area, and the fields within each event. A brief description is provided for each field. Every event generated includes common data, which collects device data.
The long, long, long list of data Microsoft gathers when Windows 10's data collection is set to 'basic'. Some... Light reading as the Windows 10 Creator's Update, which is now available, installs (you can also wait until 11 April to get it through Windows Update).