It's not an empty line at the end of the file, as a lot of people seem to believe. It's a newline character at the end of each line. A text file with n lines has exactly n newline characters, so a text file with no lines has no newline characters. (That said, many text editors do display an empty line at the end of a proper text file, even though that line doesn't actually exist.)Originally Posted by rstanley
(DOS/Windows sometimes treats the newline character sequence (CR LF) as a line separator, rather than a line terminator, which makes it impossible to distinguish between a file with zero lines of text and a file with one zero-length line of text. POSIX doesn't have that problem.)
Either way, the C and C++ standards require that all lines in a source file to end in a newline character(s). (I mention C++ because the source file in OP's screenshot is Untitled6.cpp, which indicates a C++ source file.)
