This is where we start getting into some math! It's very basic, but incredibly useful. Check out this table, provided by PHP.net:

Example | Name | Result |
---|---|---|

`$a + $b` |
Addition | Sum of `$a` and `$b` |

`$a - $b` |
Subtraction | Difference of `$a` and `$b` |

`$a * $b` |
Multiplication | Product of `$a` and `$b` |

`$a / $b` |
Division | Quotient of `$a` and `$b` |

`$a % $b` |
Modulus | Remainder of `$a` divided by `$b` |

The **modulus** operator is usually a pretty confusing concept at first, but mathforum.org provides a pretty good explanation here:

The "mod" operator in computer languages is simply the remainder. For example,

`17 mod 3 = 2`

because

`17 / 3 = 5 rem 2`

which in turn means

`17 = 3 * 5 + 2`

Here is an example of how you would use one of the above arithmetic operators:

<?php $birthYear = 1988; $thisYear = date('Y'); $myAge = ($thisYear - 1988); echo $myAge; ?>

Feel free to experiment with all of the above arithmetic operators with some PHP using the practice.php page provided in this folder.

©2019 Brad Hussey