PHP Fundamentals

Chapter 4: Variables and Data Types

4.1 Variables

Variables store data and are prefixed with $.

$name = "John";
$age = 30;
$price = 19.99;
$isActive = true;

4.2 Data Types

PHP supports various data types.

Scalar Types:

• String - Text data
• Integer - Whole numbers
• Float - Decimal numbers
• Boolean - true/false

Compound Types:

• Array - Ordered collection
• Object - Instance of a class

4.3 Type Casting

Convert between data types explicitly.

$number = (int) "123";
$string = (string) 123;
$float = (float) "3.14";