Operators

Operators take one or two values (or variables), perform an operation, and return a value. Let's check out a simple example of using an operator, just to clarify the terminology.

>>> 1 + 2

3

In this code:

Instead of using the values 1 and 2 directly in the operation, you can use variables. You can also use a variable to store the result of the operation, as the following example demonstrates:

>>> var a = 1; 
>>> var b = 2; 
>>> a + 1 

2

>>> b + 2 

4

>>> a + b 

3

>>> var c = a + b; 
>>> c 

3

The following table lists the basic arithmetic operators:

When you type var a = 1; this is also an operation; it's the simple assignment operation and = is the simple assignment operator.

There is also a family of operators that are a combination of an assignment and an arithmetic operator. These are called compound operators. They can make your code more compact. Let's see some of them with examples.

>>> var a = 5;
>>> a += 3;

8

In this example a += 3; is just a shorter way of doing a = a + 3;

>>> a -= 3;

5

Here a -= 3; is the same as a = a - 3;

Similarly:

>>> a *= 2;

10

>>> a /= 5;

2

>>> a %= 2;

0

In addition to the arithmetic and assignment operators discussed above, there are other types of operators, as you'll see later in this and the following chapters.