Typically, to learn a new application program in 40 hours, you might be advised to work your way through the menu and toolbars of commands to familiarize yourself with available functions. While to learn a new programming language, you would be told to take a straightforward problem to solve, and write a program to solve it using only those functions that you needed.
Mathematica contains perhaps the most extensive programming language extant, with over 4000 built-in general-purpose functions and an auxiliary website with over 300,000 additional mathematical functions.Mathematica's programming environment, affectionately called the Front End, is so user-friendly that it's similar to an application program like Word or Excel. We advocate learning Mathematica in the style of the "need to know" basis used for programming languages, using guidance from books such as this one.
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