__An alphabet is a finite nonempty set of symbols. Conventionally we use the symbol summession symbol for an alphabet, common alphabets include :__

**Alphabets :**__summession symbol = {0,1}, the binary alphabet__

**1.**__summession symbol = {a,b...z}, the set of the lower case letters.__

**2.**__The set of all ASCII characters or the set of all printable ASCII characters.__

**3.**__If summession symbol is an alphabet, we can express the set of all strings of a certain length from that alphabet by using an exponential notation. We define summession power of k to be the set of strings of length K, each of which symbols is in summession symbol.__

**Powers of an Alphabet :**__If summession symbol = {0, 1}, then power of 1 summession symbol = {0,1}__

**Example :**
power of 2 summession symbol = {00, 01, 10, 11}

power of 3 summession symbol = {000, 001, 010, 011, 100, 101, 110, 111}

And so on.