Floating-point arithmetics adopted this from the extended reals (usually denoted as ℝ̅): https://en.wikipedia.org/wiki/Extended_real_number_line https://en.wiki

Floating-point arithmetics adopted this from the extended reals (usually denoted as ℝ̅): https://en.wikipedia.org/wiki/Extended_real_number_line https://en.wikipedia.org/wiki/Extended_real_number_line (see Arithmetic operations there)