Operators are used to perform operations on variables and values.

**For example:**

$num=10+20;//+ is the operator and 10,20 are operands

In the above example, + is the binary + operator, 10 and 20 are operands and $num is variable.

**PHP divides the operators in the following groups:**

- Arithmetic Operators
- Assignment Operators
- Bitwise Operators
- Comparison Operators
- Incrementing/Decrementing Operators
- Logical Operators
- String Operators
- Array Operators
- Conditional assignment operators

We can also categorize operators on behalf of operands. They can be categorized in 3 forms:

**Unary Operators:**works on single operands such as ++, — etc.**Binary Operators:**works on two operands such as binary +, -, *, / etc.**Ternary Operators:**works on three operands such as “?:”.

## PHP Arithmetic Operators

The PHP arithmetic operators are used with numeric values to perform common arithmetical operations, such as addition, subtraction, multiplication etc.

Operator | Name | Example | Explanation |
---|---|---|---|

+ | Addition | $a + $b | Sum of operands |

– | Subtraction | $a – $b | Difference of operands |

* | Multiplication | $a * $b | Product of operands |

/ | Division | $a / $b | Quotient of operands |

% | Modulus | $a % $b | Remainder of operands |

** | Exponentiation | $a ** $b | $a raised to the power $b |

## PHP Assignment Operators

The PHP assignment operators are used with numeric values to write a value to a variable.

The basic assignment operator in PHP is “=”. It means that the left operand gets set to the value of the assignment expression on the right.

Operator | Name | Example | Explanation |
---|---|---|---|

= | Assign | $a = $b | The value of right operand is assigned to the left operand. |

+= | Add then Assign | $a += $b | Addition same as $a = $a + $b |

-= | Subtract then Assign | $a -= $b | Subtraction same as $a = $a – $b |

*= | Multiply then Assign | $a *= $b | Multiplication same as $a = $a * $b |

/= | Divide then Assign (quotient) | $a /= $b | Find quotient same as $a = $a / $b |

%= | Divide then Assign (remainder) | $a %= $b | Find remainder same as $a = $a % $b |

## PHP Bitwise Operators

The bitwise operators are used to perform bit-level operations on operands. These operators allow the evaluation and manipulation of specific bits within the integer.

Operator | Name | Example | Explanation |
---|---|---|---|

& | And | $a & $b | Bits that are 1 in both $a and $b are set to 1, otherwise 0. |

| | Or (Inclusive or) | $a | $b | Bits that are 1 in either $a or $b are set to 1 |

^ | Xor (Exclusive or) | $a ^ $b | Bits that are 1 in either $a or $b are set to 0. |

~ | Not | ~$a | Bits that are 1 set to 0 and bits that are 0 are set to 1 |

<< | Shift left | $a << $b | Left shift the bits of operand $a $b steps |

>> | Shift right | $a >> $b | Right shift the bits of $a operand by $b number of places |

## PHP Comparison Operators

The PHP comparison operators are used to compare two values (number or string):

Operator | Name | Example | Explanation |
---|---|---|---|

== | Equal | $a == $b | Return TRUE if $a is equal to $b |

=== | Identical | $a === $b | Return TRUE if $a is equal to $b, and they are of same data type |

!== | Not identical | $a !== $b | Return TRUE if $a is not equal to $b, and they are not of same data type |

!= | Not equal | $a != $b | Return TRUE if $a is not equal to $b |

<> | Not equal | $a <> $b | Return TRUE if $a is not equal to $b |

< | Less than | $a < $b | Return TRUE if $a is less than $b |

> | Greater than | $a > $b | Return TRUE if $a is greater than $b |

<= | Less than or equal to | $a <= $b | Return TRUE if $a is less than or equal $b |

>= | Greater than or equal to | $a >= $b | Return TRUE if $a is greater than or equal $b |

<=> | Spaceship | $a <=>$b | Return -1 if $a is less than $b Return 0 if $a is equal $b Return 1 if $a is greater than $b |

## PHP Increment / Decrement Operators

- The PHP increment operators are used to increment a variable’s value.
- The PHP decrement operators are used to decrement a variable’s value.

Operator | Name | Example | Explanation |
---|---|---|---|

++ | Increment | ++$a | Increment the value of $a by one, then return $a |

$a++ | Return $a, then increment the value of $a by one | ||

— | decrement | –$a | Decrement the value of $a by one, then return $a |

$a– | Return $a, then decrement the value of $a by one |

## PHP Logical Operators

The PHP logical operators are used to combine conditional statements.

Operator | Name | Example | Explanation |
---|---|---|---|

and | And | $a and $b | Return TRUE if both $a and $b are true |

Or | Or | $a or $b | Return TRUE if either $a or $b is true |

xor | Xor | $a xor $b | Return TRUE if either $ or $b is true but not both |

! | Not | ! $a | Return TRUE if $a is not true |

&& | And | $a && $b | Return TRUE if either $a and $b are true |

|| | Or | $a || $b | Return TRUE if either $a or $b is true |

## PHP String Operators

PHP has two operators that are specially designed for strings.

Operator | Name | Example | Explanation |
---|---|---|---|

. | Concatenation | $a . $b | Concatenate both $a and $b |

.= | Concatenation and Assignment | $a .= $b | First concatenate $a and $b, then assign the concatenated string to $a, e.g. $a = $a . $b |

## PHP Array Operators

The PHP array operators are used to compare arrays.

Operator | Name | Example | Explanation |
---|---|---|---|

+ | Union | $a + $y | Union of $a and $b |

== | Equality | $a == $b | Return TRUE if $a and $b have same key/value pair |

!= | Inequality | $a != $b | Return TRUE if $a is not equal to $b |

=== | Identity | $a === $b | Return TRUE if $a and $b have same key/value pair of same type in same order |

!== | Non-Identity | $a !== $b | Return TRUE if $a is not identical to $b |

<> | Inequality | $a <> $b | Return TRUE if $a is not equal to $b |

## PHP Conditional Assignment Operators

The PHP conditional assignment operators are used to set a value depending on conditions:

Operator | Name | Example | Explanation |
---|---|---|---|

?: | Ternary | $x = expr1 ? expr2 : expr3 | Returns the value of $x. The value of $x is expr2 if expr1 = TRUE.The value of $x is expr3 if expr1 = FALSE |

?? | Null coalescing | $x = expr1 ?? expr2 | Returns the value of $x. The value of $x is expr1 if expr1 exists, and is not NULL.If expr1 does not exist, or is NULL, the value of $x is expr2.Introduced in PHP 7 |