What are operators in PHP? Provide examples of arithmetic, assignment, and comparison operators.

In PHP, operators are symbols or special characters that perform operations on one or more operands (values or variables). They are used to manipulate data, perform calculations, assign values, compare values, and control program flow. Let's explore the different types of operators in PHP:

1. Arithmetic Operators:

* Arithmetic operators perform basic mathematical calculations.
* Examples:
```
php`$x = 10;
$y = 5;
$sum = $x + $y; // Addition
$difference = $x - $y; // Subtraction
$product = $x * $y; // Multiplication
$quotient = $x / $y; // Division
$remainder = $x % $y; // Modulo (remainder of division)`
```
2. Assignment Operators:

* Assignment operators are used to assign values to variables.
* Examples:
```
php`$x = 10; // Assigning a value
$y += 5; // Equivalent to $y = $y + 5 (add and assign)
$z -= 3; // Equivalent to $z = $z - 3 (subtract and assign)
$a *= 2; // Equivalent to $a = $a 2 (multiply and assign)
$b /= 4; // Equivalent to $b = $b / 4 (divide and assign)`
```
3. Comparison Operators:

* Comparison operators compare values and return a boolean result (true or false).
* Examples:
```
php`$x = 10;
$y = 5;
$isGreater = ($x > $y); // Greater than
$isSmaller = ($x < $y); // Less than
$isEqual = ($x == $y); // Equal to
$isNotEqual = ($x != $y); // Not equal to
$isGreaterOrEqual = ($x >= $y); // Greater than or equal to
$isSmallerOrEqual = ($x <= $y); // Less than or equal to`
```

These examples showcase some of the commonly used arithmetic, assignment, and comparison operators in PHP. However, PHP supports many other operators, including logical operators (`&&`, `||`, `!`), string concatenation operator (`.`), increment and decrement operators (`++`, `--`), and more. These operators play a crucial role in performing various operations and implementing complex logic in PHP programs.