Some typewriter ribbons were inked in black and red stripes, each being half the width and running the entire length of the ribbon. A lever on most machines allowed switching between colors, which was useful for bookkeeping entries where negative amounts were highlighted in red. The red color was also used on some selected characters in running text, for emphasis. When a typewriter had this facility, it could still be fitted with a solid black ribbon; the lever was then used to switch to fresh ribbon when the first stripe ran out of ink. Some typewriters also had a third position which stopped the ribbon being struck at all.
