c. The 256 Bits in American Standard Code For Information Interchange I.
The seven significant bits that ASCII assigns, provide 27 (2 x 2 x 2 x 2 x 2 x 2 x 2) or
128 possible combinations of 0s and 1s. An eighth bit is either ignored or used to check
accuracy. So, there are 28 or 256 possible combinations of zeros and ones.
d. Eight Bits or One Byte to Represent Letters, Numbers, Symbols, or
Characters. You will recall that eight bits equal one byte, a byte being the smallest unit
recognizable to humans. In ASCII, although there are seven significant bits to represent
input, there are still a total of eight bits per letter, number, symbol, or character. The
ASCII code numbers that signal the specific alphanumeric character, that is, A, B, C or 1,
2, 3 have been highlighted with boldfaced type in the figure below.
Figure 1-27. The boldfaced binary bits represent the letters of the alphabet in ASCII.