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incomprehensibly difficult text. requires ph.d to even understand. someone please translate it to a human language.

also it is not a tutorial!

I don't want to know it, this article is to long for my attention span...

Okay, over my head as well.
But it's important to know a *few* things at least about floating point calculations if you're a developer -- particularly if you ever deal with currency (and we pretty much all do...), because of the tiny error that's basically unavoidable in floating point calculations.

For example, try this in Java:
float result = 1.68f - 1.10f;
System.out.println( "result will be 0.58 of course... right?: " + result );

Nope. "I know", you say, "use double instead of float... lots more significant digits!".
Well, try it.

This is a huge gotcha. Floating point math is fine for most things, where a tiny fraction difference won't matter, but for currency it's simply dangerous.
There are multiple ways to dodge the "missing pennies" problem:
* Store currencies as pennies, and just add the decimal point for display (so all your arithmetic will be int arithmetic).
* Use BigDecimal for currency

@theory

.NET has a nice decimal type which is great for currency. It has 128bits of precision.