However, in 1946 Arthur Burks used the terms "mantissa" and "characteristic" to describe the two parts of a floating-point number (Burks "et al.") and that usage remains common among computer scientists today. "Mantissa" and "characteristic" have long described the two parts of the logarithm found on tables of common logarithms. While the two meanings of "exponent" are analogous, the two meanings of "mantissa" are not equivalent. For this reason, the use of "mantissa" for "significand" is discouraged by some including the creator of the standard, William Kahan and prominent computer programmer and author of "The Art of Computer Programming", Donald E. Knuth