Mathematics Stack Exchange is a question and answer site for people studying math at any level and professionals in related fields. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

What does "String" mean in context of counting theory ? For example :

There are 8 binary strings of length 3 .

What does binary and length signify here ?

Edit : I want to specifically why it is called a String ?

share|cite|improve this question
It says there are $8$ three-letter "words" using the alphabet $\{0,1\}$. Here are a few: $000$, $001$, $010$, $011$, $100$, three more to go. – André Nicolas Aug 4 '12 at 6:30
@AndréNicolas I edited the question slightly . I want to know why it is called String ? – Geek Aug 4 '12 at 6:32
For variety. Like a string of beads. "Sequence" is common too, kinda boring. "Word" is freqently used also. All of these terms convey the notion that order is important. – André Nicolas Aug 4 '12 at 6:35
up vote 2 down vote accepted

binary string means $\textit{a sequence of 0's and 1's}$ and the length defines the number of elements in the sequence.

Like $10011$ is a binary string of length $5$, $110011100$ is a binary string of length $9$ etc.

share|cite|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.