[dv8]

I've run into something very strange.
I wrote a small loop to start from -1 and stop at 0 by using a step of .05.

Actionscript:

for (var j = -1; j <= 0; j += .05) {
	trace(j);
}

However my output is not what to be expected

Code:

-1
-0.95
-0.9
-0.85
-0.8
-0.75
-0.7
-0.65
-0.6
-0.55
-0.5
-0.45
-0.4
-0.35
-0.3
-0.25
-0.2
-0.15
-0.0999999999999997
-0.0499999999999997

Why oh why did -0.15 + .05 equal -0.0999999999999997?

Is this bad math? Is this correct math and why?