# 15.8: String Operations

- Page ID
- 16881

In general, you can’t perform mathematical operations on strings, even if the strings look like numbers, so the following are illegal:

'2'-'1' 'eggs'/'easy' 'third'*'a charm'

The `+` operator works with strings, but it might not do what you expect: it performs **concatenation**, which means joining the strings by linking them end-to-end. For example:

first = 'throat' second = 'warbler' print first + second

The output of this program is `throatwarbler`

.

The * operator also works on strings; it performs repetition. For example, `'Spam'*3`

is `'SpamSpamSpam'`

. If one of the operands is a string, the other has to be an integer.

This use of + and * makes sense by analogy with addition and multiplication. Just as `4*3`

is equivalent to `4+4+4`

, we expect `'Spam'*3`

to be the same as `'Spam'+'Spam'+'Spam'`

, and it is. On the other hand, there is a significant way in which string concatenation and repetition are different from integer addition and multiplication. Can you think of a property that addition has that string concatenation does not?