Resource readers are used to read a stream of data from resource files in a particular format. Implement this interface when you want to control the way in which a resource file is read (for example, if the resource file was written by using a customized System.Resources.ResourceWriter) or if you are using a non-standard format or file type for storing resources. Otherwise, use the default System.Resources.ResourceReader class, which reads resource information from binary .resources files, or the System.Resources.ResXResourceReader class, which reads resource information from XML resource (.resx) files.