$ echo -n "1234" | od -t x # Little Endian
0000000 34333231
0000004
$ echo -n "1234" | xxd -e # Print Little Endian
00000000: 34333231 1234
$ echo -n "1234" | xxd # Print Big Endian
00000000: 3132 3334 1234
$ echo -n "1234" | hexdump -ve '1/1 "%.2x"' # Print Big Endian
31323334