$ByteOrdering gives the native ordering of bytes in binary data on your computer system.
Possible values of $ByteOrdering are +1 and -1.
+1 corresponds to big endian (appropriate for 680x0 and many other processors); -1 corresponds to little endian (appropriate for x86 processors).
+1 corresponds to having the most significant byte first; -1 to having the least significant byte first.
+1 is the order obtained from IntegerDigits[n, 256].
$ByteOrdering gives the default setting for the ByteOrdering option in Import and Export.
See Section 2.14.5.
See also: $ProcessorType.
New in Version 4.