## JavaScript Mathematical Operators

To perform calculations in our code, we can use **operators**. You are likely familiar with many common operators from studying maths at school.

Once you feel comfortable with mathematical operators, you’ll never need to do mental arithmetic again! At least, as long as you have a computer nearby…

**Arithmetic Operators**

There are a many arithmetic operators that can be used to form JavaScript

expressions

.

You may be familiar with operators such as:

- + Addition
- – Subtraction
- * Multiplication
- / Division

These operators can be applied to

data

to create expressions. The data could be literal values, or

variables

that hold these values. We can also store the result of the expressions in variables!

const personOneScore = 40

const personTwoScore = 50

const sumOfScores = personOneScore + personTwoScore

const differenceOfScores = personOneScore – personTwoScore

const doubleScore = personOneScore * 2

const halfScore = personTwoScore / 2

Even though there are multiple pieces of data in expressions like these, when JavaScript performs the operations for us, the end result will always be a *single* value. Using operators to calculate a result is an example of

evaluation

.

A piece of data used by an operator is called an **operand**. In the expression 4 * 25, 4 is the first operand, and 25 is the second.

We have two less familiar – but still very useful –

operators

to cover.

## Modulo and Exponents

JavaScript has a **modulo** operator `%`

that will divide the first

operand

by the second, then

evaluate

to a number showing the *remainder*. const` remainder `

=` `

7` `

%` `

3` `

*// 1*

The modulo operator is great for finding out whether numbers are even or odd. Even numbers will produce a remainder of `0`

when divided by `2`

, whereas odd numbers will leave a remainder of `1`

when divided by `2`

.

The **exponentiation** operator, `**`

, multiplies the first operand by itself a number of times equal to the second operand (the *exponent*). const` exponent `

=` `

3`const`

` result `

=` `

2` `

**` exponent `

*// 8, or 2 * 2 * 2*

There are lots of ways of conveying exponent expressions in human language – for example, “two to the power of three” or “two to the third power