Computing the Lengths of Strings

Recall that strings are a datatype for storing text and can be created by writing some characters in between single or double quotes:

>>> "CS 515-A"
'CS 515-A'
>>> 'CS 515-A'
'CS 515-A'

In this lesson, you will be learning more ways to use strings. In Python, you can think of strings as sequences of characters and the length of a string is the number of characters. To compute the length of a string, you can use the len() function. You can pass the len() function a string value (or a variable containing a string), and the function evaluates the number of characters in that string.

>>> len("hello")
5
>>> s1 = 'CS 515-A!'
>>> len(s1)
9
>>> len('')
0

The string ‘’ contains no characters and is called an (or “the”) empty string.