Binary Numbers
 

All digital computers represent data as a collection of bits. A bit is the smallest possible unit of information. It can be in one of two states - off or on, 0 or 1.  All computer data - a text file on disk, a program in memory, a packet on a network - is a collection of bits.


 



If one bit has two different states, how many states do two bits have?


The answer is four.

Likewise, three bits have eight states. For example, if a computer display had eight colors available, and you wished to select one of these to draw a diagram in, three bits would be sufficient to represent this information. Each of the eight colors would be assigned to one of the three-bit combinations. Then, you could pick one of the colors by picking the right three-bit combination.

 



A common and convenient grouping of bits is the byte or octet, composed of eight bits.


If two bits have four combinations, and three bits have eight combinations, how many combinations do eight bits have?


 

(c) Shilpa Sayura Foundation 2006-2017