It is common knowledge that floating point numbers (`float`) are tricky. When misused, floats may lead to construction disaster – I will mention some notable accidents. But mainly, I will dig the topic from Python interface and rounding methods (`int` vs `round`, `divmod`, `math` library), via special symbols (`NaN`, `Inf`, `-0.0`, …), invoking different processor modes (`FLT_ROUNDS`), down to the bits of IEEE 754 standard.