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Mathematica
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Building Systems with Mathematica
Mathematica has everything you need to create complete systems for technical and non-technical applications.
Combinatorica and WorldPlot are two examples of standard add-on packages that come with full versions of Mathematica.
This loads the Combinatorica system.
This uses functions set up by the package.
WorldPlot is another standard add-on package that comes with Mathematica.
Optica is a large Mathematica package for doing optical engineering.
Mathematica has made possible a new generation of notebook-based educational courseware.

You can use palettes and buttons to build custom user interfaces.
Technical Trader is a Mathematica system for financial analysis.
Technical Trader uses palettes and buttons to build a custom user interface.

Clicking on a button in Technical Trader can generate a notebook of data.
Historical Daily Data for Microsoft (MSFT)High-Low-Open-Close

Summary Statistics
You can create complete applications and user interfaces directly in Mathematica.