# 1.4: Arithmetic operators

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After “Hello, World”, the next step is arithmetic. Python provides operators, which are special symbols that represent computations like addition and multiplication.

The operators +, -, and * perform addition, subtraction, and multiplication, as in the following examples:

>>> 40 + 2
42
>>> 43 - 1
42
>>> 6 * 7
42


The operator / performs division:

>>> 84 / 2
42.0


You might wonder why the result is 42.0 instead of 42. I’ll explain in the next section.

Finally, the operator ** performs exponentiation; that is, it raises a number to a power:

>>> 6**2 + 6
42


In some other languages, ^ is used for exponentiation, but in Python it is a bitwise operator called XOR. If you are not familiar with bitwise operators, the result will surprise you:

>>> 6 ^ 2
4


I won’t cover bitwise operators in this book, but you can read about them at http://wiki.python.org/moin/BitwiseOperators.

This page titled 1.4: Arithmetic operators is shared under a CC BY-NC 3.0 license and was authored, remixed, and/or curated by Allen B. Downey (Green Tea Press) .