• scientific notation with fraction F and exponent E
• numbers have form F × 2^E, where both F and E can be -ve
• INFINITY = representation for ∞ and -∞ (e.g. 1.0/0)
• NAN = representation for invalid value (e.g. sqrt(-1.0))

In binary, exponent is represented relative to a bias value B

• if the unsigned exponent value is e, the actual value is e-B