A string can be thought of as a list of characters.

Like any other list, each character in a string has an index. Consider the string

favorite_fruit = "blueberry"

We can select specific letters from this string using the index. Let’s look at the first letter of the string.

print(favorite_fruit[1])
# => 'l'

Whoops, is that the first letter you expected? Notice that the letter at index 1 of "blueberry" isn’t b, it’s l. This is because the indices of a string start at 0. b is located at the zero index and we could select it using:

print(favorite_fruit[0])
# =>'b'

It’s important to note that indices of strings must be integers. If you were to try to select a non-integer index we would get a TypeError:

print(favorite_fruit[1.5])
# => Traceback (most recent call last):
# =>  File "<stdin>", line 1, in <module>
# =>  TypeError: string indices must be integers, not float