Floating-point: “The leading 1 is 'implicit' in the significand.” — …huh?

Question

I\'m learning about the representation of floating-point IEEE 754 numbers, and my textbook says:

To pack even more bits into the significand, IEEE 754

Answer 1

It may also be helpful to note that we are dealing in binary representations of a number. The reason that the first digit of a normalized binary number (that is, no leading zeroes) has to be 1 is that 1 is the only non-zero value available to us in this representation. So, the same would not be true for, say, base-three representations.