Mathematica 5.1 is the latest version of the flagship software package published by Wolfram Research. It is a very powerful tool for teaching and learning mathematics but reached a state of maturity in that respect several upgrades ago. The software is also used extensively in research and development both in universities and industry/business. In this and the most recent upgrades the thrust has been mainly in the areas of numerical computations speed improvements data handling visualization and web connection. For symbolic computation which is perhaps of most interest in the classroom the main advances have been made in the area of piecewise functions: their construction and interaction with other functions and mathematical operations. In this review I give examples of the new piecewise function the subset function and the enhanced function for computing the exponential of a matrix.
