Backspace is the keyboard key ( sometimes labeled as : ) that originally pushed the typewriter carriage one position backwards , and for modern computer screens , moves the cursor one position backwards , deletes the preceding character , and shifts back the text after it by one position . Backspace is the keyboard key that originally pushed the typewriter carriage one position backwards , and in modern computer displays moves the cursor one position backwards , deletes the preceding character , and shifts back the text after it by one position .