Graphing calculator
From Academic Kids

 For the software tool of the same name, see Graphing Calculator.
A graphing calculator is a special kind of scientific/engineering calculator that is able to display and/or analyze mathematical function graphs. Also, graphing calculators can show several lines of text and numbers at a time. Some graphing calculators have color displays.
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History
The Japanese company Casio introduced graphing calculators with its fx7000G in 1985.
After Casio, Hewlett Packard followed shortly in the form of the HP28C. This was followed by the HP28S (1988), HP48SX (1990), HP48S (1991), HP48G/GX (1994), HP38G (1995), HP39G (199x), HP40G (199x), HP49G (1999), and the HP49G+ and HP48GII (2003). The current topofthe line model, HP49G+, features a Computer Algebra System (CAS), which lets the user perform many types of symbolic computations, like derivation and integration of functions in their general algebraic forms—e.g., d/dx(y=cos(x−2)+3x²). The HP28 and 48 range were primarily meant for the professional science/engineering markets; the HP38/39/40 were sold in the high school/college educational market; while the HP49 series cater to both educational (college major and university level) and professional customers.
Texas Instruments has produced models of graphing calculators since 1990, the oldest of which was the TI81. Some of the newer calculators are just like it, only with larger memories, such as the TI82, TI83 series, (including the TI83, TI83 Plus, and TI83 Plus Silver Edition), and the TI84 Plus series (including the TI84 Plus and TI84 Plus Silver Edition). Other models, designed to be appropriate for students 10–14 years of age, are the TI80 and TI73 series (including the TI73 and TI73 Explorer). Other TI graphing calculators have been designed to be appropriate for calculus, namely the TI85, TI86, and TI89 series (including the TI89 and TI 89 Titanium; the latter two also featuring a CAS, like the HP49 models). Still others are models with a computer keyboard: the TI92 series, including the TI92, TI92 Plus, and Voyage 200.
Besides the offerings from the two major contenders in this market, HP and TI, there are graphing calculators available from Casio and Sharp Corporation.
Graphing calculators in schools
Because of their large set of features and ease of use, graphing calculators are very commonly used in schools. Many vendors, especially Casio, market their graphing calculators primarily for educational use. Casio has focused its efforts at the high school/junior college user segment, most of their calculators offering relatively easytouse graphing features (some models incorporating a threecolor display) without some of the most complex/flexible mathematical functions and programming languages found in the usually more expensive university/engineering calculators. However, an exception to this is the FX 1.0/2.0 series, of which the 2.0 models incorporate a Computer Algebra System (CAS) and a significantly improved version of Casio's BASIClike calculator programming language. Texas Instruments is Casio's chief competitor in educational graphing calculators.
Many high school mathematics teachers allow and even encourage their students to use graphing calculators in class. This describes the general policy e.g. in the Canada or United States educational systems. However, in other countries, calculators with "too powerful" features are generally forbidden. As an example, in Finland it is forbidden to use calculators with symbolic calculation (CAS) or 3D graphics features in the matriculation exam. In Norway, calculators with wireless communication capabilities, such as IR links, have been banned at some technical universities. The College Board of the United States permits the use of most graphing calculators that do not have a QWERTYstyle keyboard for its AP and SAT exams, but IB schools do not permit the use of calculators with computer algebra systems on its exams.
See also
 GraphCalc – A free graphical calculator emulator for Linux and Microsoft Windows
 List of calculators
 Personal Digital Assistant (PDA)
 Calculator programming
External links
 Casiocalc.org (http://www.casiocalc.org) – A forum for discussing Casio calculators
 ticalc.org (http://www.ticalc.org) – A comprehensive archive of TI graphing calculator programs
 UnitedTI (http://www.unitedti.org) – A TI calculator programming community's website
 Datamath Calculator Museum (http://www.datamath.org) – An Internet museum about calculators (with an emphasis on TI's models).
 http://www.rskey.org – Another Internet museum about calculators.fr:Calculatrice graphique