In the beginning, Texas Instruments found a solid formula to
produce a graphing calculator. The TI-81, the first of Texas
Instrument’s graphing calculators, was released in 1990, and had
a 2MHz version of the widely popular Zilog Z80 microprocessor
with just 2.4 kB of RAM. These calculators could solve
trigonometric, exponential, logarithmic functions, etc.,
numerically, and produce graphs plus perform many Linear Algebra
matrix manipulations. Since then, we have seen many iterations
of this calculator, the TI-80 family and the TI-73 series, most
of which feature "Plus (+)" versions. But most of these
calculators did not change the original 96X64-pixel screen or
any of the original functions or features, just added user
memory, RAM, and faster Zilog Z80 processors. The TI-84+ C SE
calculator – it's going to happen, but will it be a radical
departure from the past? Although the numbering system is a bit
misleading, the TI-80 was released in 1995 as a calculator meant
for middle schoolers, and used a slow 980kH