Have you performed simple arithmetic operations like 0.1 + 0.2? You might have gotten something strange: 0.1 + 0.2 = 0.30000000000000004.
Floating-point arithmetic is important to understand at least vaguely since it’s a pretty leaky abstraction. Fortunately, we don’t need a “✨Member-only story” on Medium to get acquainted with the underlying concepts.
Ugh, i thought this was a question, not a link. So i spent time googling for a good tutorial on floats (because I didn’t click the link)…
Now i hate myself, and this post.
Don’t hate yourself. At least you searched it properly. See it this way, you learned from a failure more than anyone who did not fail. You are now stronger!
It’s how CPUs do floating point calculations. It’s not just javascript. Long story short, a float is stored in the format of one bit for the +/-, some bits for a base value (mantissa), and some bits for the exponent. As a result, some numbers aren’t quite representable exactly.