CRLF is a text file format converter. CRLF stands for carriage return line feed. The difficulty with transporting otherwise innocuous text files from one platform to another is precisely the manner in which the various platforms treat that CRLF sequence.
CRLF was originally a double signal sent to telex machines to get the paper carriage back to column 0 (carriage return) and scroll up one line - (line feed). This is unnecessary in the era of word processing.