31Don’t confuse REAL variables with the real numbers. REAL variables take values that are finite approximations to real numbers and take values that are a subset of the rational numbers. This approximation becomes better with increasing the amount of memory allocated to REALs. In most computing environments, REALs are allocated 4 or 8 bytes of memory, in which case they approximate real numbers with, more or less, 7 or 17 significant digits, respectively.