# PHP Variable Scope

The scope of a variable in PHP is the context in which it is defined and accessible. In other words, it determines where a variable can be used in the code and whether it is accessible.

In PHP, there are two types of variable scope:

① **Local scope**

② **Global scope**

**Local scope** means that a variable defined within a function or block of code is only accessible within that function or block of code.

A variable defined outside of a function or block of code has a **global scope** and can be accessed from anywhere in the code.

The ***global*** keyword in PHP also allows you to access variables from the global scope within a function or block of code. This allows you to use a variable defined in the global scope within a function or block of code without having to pass it as an argument to the function.

Want an example of how variable scope works in PHP? Here you go.

```php
<?php
// Global scope
$city_global = 'Kampala';

function myFunction() {
  // Local scope
  $city_local = 'Lagos';

  echo $city_local; // Outputs Lagos
  echo $city_global; // Outputs Kampala (accessing a variable from the global scope)
}

myFunction();

echo $city_local; // Undefined variable error
```

$city\_global is defined in the global scope in this example and is accessible from within the myFunction function. $city\_local is defined in the myFunction function and is only accessible within it. If you try to access $city\_local outside of the function, an undefined variable error will occur.

```plaintext
   global scope
  ------------
  |          |
  | function |
  |          |
  ------------
     local scope
```

In this example, the `global scope` represents the main program or script that is running. The `function` represents a function defined within the program. The `local scope` represents variables that are defined within the function and are only accessible within that function.

Variables defined in the `global scope` are accessible to all functions and can be accessed and modified by them. Variables defined in the `local scope` are only accessible within the function in which they are defined, and they cannot be accessed or modified by functions outside of that function.

I hope this helps! Please let me know if you have any further questions in the comments below.