Php Data Types

PHP Data Types

PHP data types are used to hold different types of data or values. PHP supports 8 primitive data types that can be categorized further in 3 types:

* Scalar Types(predefined):
It holds only single value. There are 4 scalar data types:

1. Boolean: The simplest data type works a like switch. It holds only two values: TRUE(1) or FALSE(0). It is often used with conditional statements.

2. Integer: It holds only whole number i.e. without decimal points. It can be either positive or negative.

3. Float: Unlike integer, it can hold numbers with a fractional or decimal point, including a negative or positive sign.

4. String: A string is a non-numeric data type. It holds letters or any alphabets, numbers, and even special characters. String values must be enclosed either within single quotes or in double quotes.

* Compound Types(user-defined):
It can hold multiple values. There are 2 compound data types:

1. Array: It can store multiple values of same data type in a single variable.

2. Object: Objects are instances of user-defined classes that can store both values and functions. They must be explicity declared.

* Special Types:
There are 2 special data types:

1. Resource: Resources are not the exact data type in PHP. Basically, these are used to store some function calls or references to external PHP resources.

2. Null: Null is a special data type that has only one value: NULL. It is case-sensitive.

Basic Programming in PHP

Example: A program to calculate sum of two numbers

<!DOCTYPE HTML>  
<html>  
<body>  
<?php  
$x=10;  
$y=6;  
echo $x + $y;  
?>  
</body>  
</html>  

Output:
16