Ti-83

The TI-83 series is a series of graphing calculators manufactured by Texas Instruments.
The original TI-83 is itself an upgraded version of the TI-82. Released in 1996, it was one of the most popular graphing calculators for students. In addition to the functions present on normal scientific calculators, the TI-83 includes many features, including function graphing, polar/parametric/sequence graphing modes, statistics, trigonometric, and algebraic functions, along with many useful applications. Although it does not include as many calculus functions, applications and programs can be written on the calculator or loaded from external sources.
The TI-83 was redesigned twice, first in 1999 and again in 2001. TI replaced the TI-83 with the TI-83 Plus in 1999. The redesign introduced a design very similar to the TI-73 and TI-83 Plus, eliminating the sloped screen that had been common on TI graphing calculators since the TI-81, and included Flash memory, enabling the device's operating system to be updated if needed, or for large new Flash Applications to be stored, accessible through a new Apps key. The Flash memory can also be used to store user programs and data. In 2001, the TI-83 Plus Silver Edition was released, which featured approximately nine times the available flash memory, and over twice the processing speed (15 MHz) of a standard TI-83 Plus, all in a translucent grey case inlaid with small "sparkles". The 2001 redesign (nicknamed the TI-83 "Parcus") introduced a slightly different shape to the calculator itself, eliminated the glossy grey screen border, and reduced cost by streamlining the printed circuit board to four units.

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