A computer algebra system (CAS) is a software program that facilitates symbolic mathematics. The core functionality of a CAS is manipulation of mathematical expressions in symbolic form.

The HP CAS system was created by Bernard Parisse, University de Grenoble, for the HP 48Gii, HP 49g+ calculators and later in HP 50g graphing calculator. The same CAS technology was later implemented on the HP 40gs. The HP CAS system offers the user a vast array of functions and abilities as well as an easy user interface.

The expressions manipulated by the CAS typically include polynomials in multiple variables; standard functions of expressions (sine, exponential, etc.); various special functions (gamma, zeta, erf, Bessel, etc.); arbitrary functions of expressions; derivatives, integrals, sums, and products of expressions; truncated series with expressions as coefficients, matrices of expressions, and so on.

Learning to use the CAS is very easy but, as with any powerful tool, truly effective use requires familiarity and time. On the HP the learning process is greatly aided by an incredibly detailed help system which offers a detailed explanation of the syntax of each function. These help pages include cross references to related functions and examples which can be pasted into the CAS with the press of a single button. Simply press HELP when selecting the function in a choose box to access the help.

**History of CAS -** Computer algebra systems began to appear in the early 1970s. Reduce, Derive, and Maxima are still commercially available software. Maxima is a freeware and is still actively being maintained. The current market leaders are Maple and Mathematica; both are commonly used by research mathematicians, scientists, and engineers. MuPAD is a commercial system too.

Learning to use CAS effectively through a combination of subtle reminders and frequency of student use, eradicating technical and mathematical difficulties: Here are some learning objectives:

- Working with variables and defined functions
- Order of operations
- Understanding and Recovering from Error messages
- Effective use of the symbolic manipulation
- Remembering CAS syntax
- Equivalence of form
- Recording work

Following backlink list where CAS were referenced on educalc.net site: