\n = LF (Line Feed) // Used as a new line character on Unix
\r = CR (Carriage Return) // Used as a new line character on Mac
\r\n = CR + LF // Used as a new line character on Windows
(char)13 = \r = CR
Environment.NewLine = any of the above code based on the operating system
// .NET provides the Environment class which provides many data based on operating systems, so if the application is built on Windows, and you use CR + LF ("\n\r" instead of Environment.NewLine) as the new line character in your strings, and then Microsoft creates a VM for running .NET applications in Unix, then there will be problem. So, you should always use Environment.NewLine when you want a new line character. Now you need not to care about the operating system.