Texas Instruments TI-83 PLUS - Manual (Page 5)

TI-83 Plus Operating the TI-83 Plus Silver Edition 2
TI-83 Plus Keyboard
Generally, the keyboard is divided into these zones: graphing keys,
editing keys, advanced function keys, and scientific calculator keys.
Keyboard Zones
Graphing — Graphing keys access the interactive graphing features.
Editing — Editing keys allow you to edit expressions and values.
Advanced — Advanced function keys display menus that access the
advanced functions.
Scientific — Scientific calculator keys access the capabilities of a
standard scientific calculator.