This CAS is compareable to Maple. The syntax is very similar. But you're able to define vaiables f. e..
The main difference is: it is "better" beacuse it is more compfortable and it is free. If you avoid binaries f. e. you will like it.
Maxima is a system for the manipulation of symbolic and numerical expressions, including differentiation, integration, Taylor series, Laplace transforms, ordinary differential equations, systems of linear equations, polynomials, and sets, lists, vectors, matrices, and tensors. Maxima yields high precision numeric results by using exact fractions, arbitrary precision integers, and arbitrarily precision floating point numbers. Maxima can plot functions and data in two and three dimensions.
You easily can integrate Maxima into emacs (imaxima, imaxima-latex), you can use wxWidgtes or wxMac to have a more compfortable GUI than x11 can offer. And you can use wxMaxima.
That offers a great funtionality, dooesn't it?