After experiments with more traditional editors, TYPER, an editor designed specifically for the online composition and editing of text, was developed. TYPER uses the 20 lines of a CRT terminal screen to implement a window onto the writer's text that can be moved at will. All normal typewriter functions are available plus special functions for the easy insertion, deletion, and modification of text. A non-destructive cursor can be moved about the screen and acts as a pointer to the text. Any printable character typed is immediately placed in the text at the position indicated by the cursor and the change is reflected on the screen. Insertion and deletion of text is accomplished with simple keystrokes. After an insertion or deletion, any extra space between words and space at the end of short lines is filled by "closing" the text. Successive words are placed so that they are separated by one space and extra space at the end of a line is filled with words from the succeeding line.Response to TYPER has been excellent. Non-programmers and even those with no computer experience learn its use quickly and are loath to go back to typewriters after using it. In addition, programmers are using it to edit their program code.