Editing Fat binary (section)

===Apple's fat binary===
A fat-binary scheme smoothed the [[Apple Macintosh]]'s transition, beginning in 1994, from [[68k]] microprocessors to [[PowerPC]] microprocessors. Many applications for the old platform ran transparently on the new platform under an evolving [[emulator|emulation scheme]], but emulated code generally runs slower than native code. Applications released as "fat binaries" took up more storage space, but they ran at full speed on either platform. This was achieved by packaging both a [[Motorola 68k|68000]]-compiled version and a PowerPC-compiled version of the same program into their executable files.<ref name="Engst_1994_1"/><ref name="Engst_1994_2"/> The older 68K code (CFM-68K or classic 68K) continued to be stored in the [[resource fork]], while the newer PowerPC code was contained in the [[data fork]], in [[Preferred Executable Format|PEF]] format.<ref name="Apple_1996_ResourceManager"/><ref name="Apple_1997_Fat"/><ref name="Apple_1997_PEF"/>

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.<ref name="Engst_1994_1"/><ref name="Engst_1994_2"/> In the era of small [[hard drive]]s, 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.