Linefeed characters are represented as ordinal 10, or hexadecimal 0x0A
Carriage returns characters are represented as ordinal 13, or hexadecimal 0x0D

File In *nix: Lines end with a single linefeed (LF) character
File In Windows: Lines end with the carriage return – linefeed combination (CRLF)

Converting file from Windows to *nix means that remove carriage return character
tr -d “\r” < windows.txt > linux.txt