The 68000-processor supports two different data types: binary and BCD Float numbers are not supported. One needs a coprocessor. I don' t know whether one exists for the 68000 processor. Data is stored in high endian format: The Z80 and x86 stores binary numbers with the LSB in the first byte, i.e. $12345678 is stored $78,$56,$34,$12 in the memory. The 68k stores it the other way around, $12,$34,$56,$78. That way to store numbers in the memory is called high endian.