HP 35s Scientific Calculator - Manual (Page 18)

1-2 Getting Started
Highlights of the Keyboard and Display
Shifted Keys
Each key has three functions: one printed on its face, a left–shifted function
(yellow), and a right–shifted function (blue). The shifted function names are printed
in yellow above and in blue on the bottom of each key. Press the appropriate shift
key (
 or  ) before pressing the key for the desired function. For example, to
turn the calculator off, press and release the  shift key, then press  .