In assembly, in order to represent an integer type, it is represented by two bytes, that is, a total of *** 16 bits. High and low 8-bit finger 16-bit memory cell;

Assembly can directly call registers, which is faster than memory. 0~7 bits are 8 low bits and 8~ 15 bits are 8 high bits, so the use of registers is more convenient.

For example, 00000000000000000, the order of the first eight zeros is 15 to 8, which is the eighth grade.

The last eight zeros are the lower eight.