Skew binary number system non-zero digits, a form called the sparse representations of numbers by Okasaki, incrementation and decrementation can be performed in constant time. Other arithmetic operations are performed by switching between the skew binary representation and the binary representation. Given a skew binary number, its value can be computed by a loop, computing the successive values of formula_4 and adding it once or twice for each formula_5 such that the formula_5th digit is 1 or 2 respectively. A more efficient method is now given, with only bit representation and one substraction. The skew binary number of the form formula_7 without 2 and
Fat binary the data fork, in PEF format. Fat binaries were larger than programs supporting only the PowerPC or 68k, which led to the creation of a number of utilities that would strip out the unneeded version. In the era of small hard drives, when 80 MB hard drives were a common size, these utilities were sometimes useful, as program code was generally a large percentage of overall drive usage, and stripping the unneeded members of a fat binary would free up a significant amount of space on a hard drive. Fat binaries were a feature of NeXT's NeXTSTEP/OPENSTEP operating system, starting