GNU nano 2: DOS Format or Mac Format on Linux

Which format (Mac or DOS) should I use on Linux PCs/Clusters? [I know the difference](https://stackoverflow.com/questions/28617814/difference-between-dos-format-and-mac-format) : - DOS format uses "carriage return" (CR or \r) then "line feed" (LF or \n). - Mac format uses "carriage return" (CR or \r) - Unix uses "line feed" (LF or \n) I also know [how to select the option](https://stackoverflow.com/questions/13368223/nano-2-0-6-saving-a-file-in-mac-format) : - AltM for Mac format - AltD for DOS format But there is no UNIX format. Then save the file with Enter.