I'm a long-time Ubuntu user (since 6.06), but I've only recently gotten into programming as part of my new job. It's mostly just dabbling in Python scripts. I also do math tutoring on the side, but I'd like to be able to provide my clients with customized tools to help them understand concepts while I'm not around.
What kind of language do you recommend that would help me create Cartesian graphs whose parameters can be easily modified by the user? For instance, the user could move a slider back and forth to adjust the slope of a line and the graph would show the effects in real time.
I do know the basics of HTML and CSS, but that's really it for the web.