efore text editors existed, computer text was punched into punched cards with keypunch machines. The text was carried as a physical box of these thin cardboard cards, and read into a card-reader. Magnetic tape or disk "card-image" files created from such card decks often had no line-separation characters at all, assuming fixed-length 80-character records. An alternative to cards was punched paper tape, which could be punched by some teleprinters (such as the Teletype), which did use special characters to indicate ends of records.
The first text editors were "line editors" oriented to teleprinter- or typewriter-style terminals without a display. Commands (often a single keystroke) effected edits to a file at an imaginary insertion point called the "cursor". Edits were verified by typing a command to print a small section of the file, and periodically by printing the entire file on a printer. On some line editors, the cursor could be moved by commands that specified the line number in the file, text strings (context) for which to search, and eventually regular expressions. Line editors were drastic improvements over keypunching. Some line editors could be used by keypunch; editing commands could be taken from a deck of cards and applied to a specified file.
When computer terminals with video screens became available, screen-based text editors (sometimes termed just "screen editors") became common. One of the earliest "full-screen" editors was O26 - which was written for the operator console of the CDC 6000 series machines in 1967. Another early full-screen editor is vi. Written in the 1970s, vi is still a standard editor on Unix and Linux operating systems. Vi and Emacs are popular editors on these systems. The productivity of editing using full-screen editors (compared to the line-based editors) motivated many of the early purchases of video terminals.