HP 33s Scientific Backspace, Keyboard-entry mode, Erases the character immediately to the left

		Keys for Clearing
Key		Description
b	Backspace.
	„	Keyboard–entry mode:
		Erases the character immediately to the left of "_" (the
		digit–entry cursor) or backs out of the current menu. (Menus
		are described in "Using Menus" on page 1–7.) If the
		number is completed (no cursor), b clears the entire
		number.
	„	Equation–entry mode:
		Erases the character immediately to the left of "¾" (the
		equation–entry cursor). If a number entry in your equation
		is complete, berases the entire number. If the number is
		not complete, berases the character immediately to the
		left of "_" (the number–entry cursor). "_" changes back to
		"¾" when number entry is complete.
	balso clears error messages, and deletes the current
	program line during program entry.
‡	Clear or Cancel.
	Clears the displayed number to zero or cancels the current
	situation (such as a menu, a message, a prompt, a catalog, or
	Equation–entry or Program–entry mode).

Getting Started 1–5