Sharepoint - When using SharePoint 2010 rest api - /_vti_bin/listdata.svc/UserInformationList, what is difference between Name and Account
The prefix i:0#.w| before the username is to identify the type of authentication.
i : for an identity claim, otherwise it will be 'c' # : for user logon name otherwise it will be $ : email address otherwise it will be % : Farm ID w : for windows authentication OR f : form based authentication.
For details please take a look in below images,
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