The number of bits used to describe (assign a value to( each of the measurements taken, is called the resolution or bit depth. With a 16-bit resolution, there are 65536 different value steps that each sample can be assigned to.
Regardless of the bit depth used, the representation is never completely accurate as some of the actual measurement values must be rounded to the nearest of the available value steps. This process is referred to as quantization.
Care must also be taken not to exceed the maximum signal level.