PHP Operators

Operators are used to calculate values using PHP.

Think of all the different operators as different buttons on a calculator. Each button calculates a value differently, and each PHP operator calculates a value differently.

If you remember simple algebra, many of these operators will look familiar to you, such as greater than (>) and less than (<). However, there are many other operators that can be used with PHP, which can be divided into four groups: Arithmetic, Assignment, Comparison and Logical operators.

Arithmetic Operators

+
Addition

-
Subtraction

*
Multiplication

/
Division

%
Modulus (the remainder value of after a division)

++
Increment (increase by a specific number)

–
Decrement (decrease by a specific number)

Examples:

2+2
5-3
5*5
20/4
5%2
$i++ (the value of the string $i would increase by 1)
$i– (the value of the string $i would decrease by 1)

Assignment Operators

Assignment operators are not used as regularly as arithmetic or comparison operators, but they are still good to know.

=
x=y is the same as x=y

+=
x+=y is the same as x=x+y

-=
x-=y is the same as x=x-y

*=
x*=y is the same is x=x*y

/=
x/=y is the same as x=x/y

.=
x.=y is the same as x=x.y

%=
x%=y is the same as x=x%y

Comparison Operators

==
Is Equal To

!=
Is Not Equal To

<
Is Less Than

>
Is Greater Than

<=
Is Less Than or Equal To

>=
Is Greater Than or Equal To

Examples:

8 == 8
1 != 2
2 < 8
8 > 2
4 <= 7
7 >= 7

Logical Operators

&&
And

||
Or

!
Not

Concentration Operator

The concentration operator is used to join multiple strings together by using a period (.).

For an example of how to use the concentration operator, see PHP strings.