My first look to Mathematica 4.0 in college lab was as an advanced calculator. I learned first at calculus handouts written by two professors: Iara Braz and Cleide Rizzatto.
We basically solved limits, derivatives and integrals. The good part is that in the standard calculus classes with pen and paper we just solve didactic books exercises without context, and with Mathematica we were able to look at more real problems and give the dirty work to Mathematica, and focus on problem-solving as an engineer really works, modeling problems as differential and integral equations, and checking graphically the solutions.
Latter I read some Mathematica books and lots of tutorials and documentations on the WEB. Mathematica online documentation is a good place to learn too, since the beginning.
Nowadays, I look at Mathematica and Wolfram Language as a mature platform, not just for calculus but to do all kinds of advanced computation and application.
Wolfram Language makes me lazy!!! :-) When I need to do something in Java, Python or JavaScript. Those other languages require a lot of boilerplate to get to the real problem-solving, most in data science!
I appreciate the responses! They are all very interesting perspectives!!
