6502.org

Here's a once-through Forth intro, with links to three further works:
(It is GForth, which might not suit all tastes.)

I'm not sure how I am supposed to react to this website:

Is it, "WOW! Only Y minutes? That's fast!!!"

or "What? I have to spend Y minutes learning this? Who has that much time?"

Sorry, the charms of Forth can't be conveyed in Y minutes. It's deeper than that, and context dependent.

I think there are steps to learning Forth. Yes, you can probably learn the "computer science basics" (definitions, loops, branches) in a few minutes. However, that is only the surface (which, to be fair, is confusing enough if you've never had to do with RPN or stacks before). There is a deeper, fundamental difference between Forth and other languages that takes far longer to grasp - you're not programming "in Forth", like you would with Python and Go, you're expanding the core Forth language into a specialized language.

That takes far longer to understand. In fact, I can feel my brain work to switch views while using my Python assembler and then the Forth emulator. But then, that could be my brain .

Another pointer, from the ChipStick project:
Forth in 7 easy steps