Many early video displays also required multiple character times to scroll the display. "The solution was to make the newline two characters: CR to move the carriage to column one, and LF to move the paper up." In fact, it was often necessary to send extra characters-extraneous CRs or NULs-which are ignored but give the print head time to move to the left margin.
Any character printed after a CR would often print as a smudge in the middle of the page while the print head was still moving the carriage back to the first position. The separation of newline into two functions concealed the fact that the print head could not return from the far right to the beginning of the next line in time to print the next character. The sequence CR+ LF was commonly used on many early computer systems that had adopted Teletype machines-typically a Teletype Model 33 ASR-as a console device, because this sequence was required to position those printers at the start of a new line. During the period of 1963 to 1968, the ISO draft standards supported the use of either CR+ LF or LF alone as a newline, while the ASA drafts supported only CR+ LF. ASCII was developed simultaneously by the International Organization for Standardization (ISO) and the American Standards Association (ASA), the latter being the predecessor organization to American National Standards Institute (ANSI).
Later, in the age of modern teleprinters, standardized character set control codes were developed to aid in white space text formatting. In particular the Morse prosign BT (mnemonic break text) represented by the concatenation of literal textual Morse codes "B" and "T" characters sent without the normal inter-character spacing is used in Morse code to encode and indicate a new line or new section in a formal text message.
In the mid-1800s, long before the advent of teleprinters and teletype machines, Morse code operators or telegraphists invented and used Morse code prosigns to encode white space text formatting in formal written text messages. This character, or a sequence of characters, is used to signify the end of a line of text and the start of a new one. Newline (frequently called line ending, end of line ( EOL), next line ( NEL) or line break) is a control character or sequence of control characters in character encoding specifications such as ASCII, EBCDIC, Unicode, etc. Newline inserted between the words "Hello" and "world"
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