Variables & Data Types

PHP Variables

Variables in PHP start with $ followed by the name. PHP is dynamically typed.

$name = "Alice";
$age = 30;
$price = 19.99;
$active = true;

Data Types

• string — text
• int — whole numbers
• float — decimal numbers
• bool — true/false
• array — ordered collections
• object — class instances
• null — no value
• resource — external resources

Type Casting

$num = (int) "42";
$str = (string) 100;

Variable Scope

Variables declared outside a function are global. Use global keyword or $GLOBALS array to access them inside functions.