What is the difference between echo, print, and print_r in PHP?

In PHP, echo, print, and print_r are used to display output, but they serve different purposes and have distinct characteristics.

Key Differences

Basic Usage

Here's how each function works with simple strings and variables −

<?php
    // Using echo
    echo "Hello World<br>";
    echo "Value: ", 25, "<br>";  // Multiple parameters allowed
    
    // Using print
    print "Hello World<br>";
    $result = print "Value: 25<br>";  // Returns 1, can be used in expressions
    echo "Print returned: $result<br>";
    
    // Using print_r with different data types
    $string = "Hello";
    $number = 42;
    $array = array("apple", "banana", "cherry");
    
    echo "print_r with string:<br>";
    print_r($string);
    echo "\nprint_r with array:<br>";
    print_r($array);
?>

Hello World
Value: 25
Hello World
Value: 25
Print returned: 1
print_r with string:
Hello
print_r with array:
Array
(
    [0] => apple
    [1] => banana
    [2] => cherry
)

Complex Data Structures

The real difference becomes apparent when working with arrays and objects −

<?php
    $data = array(
        "name" => "John",
        "age" => 25,
        "skills" => array("PHP", "JavaScript", "Python")
    );
    
    echo "Using echo:<br>";
    echo $data;  // Will show "Array" only
    
    echo "\nUsing print:<br>";
    print $data;  // Will show "Array" only
    
    echo "\nUsing print_r:<br>";
    print_r($data);  // Shows complete structure
?>

Using echo:
Array
Using print:
Array
Using print_r:
Array
(
    [name] => John
    [age] => 25
    [skills] => Array
        (
            [0] => PHP
            [1] => JavaScript
            [2] => Python
        )
)

Conclusion

Use echo for fast output of strings and variables, print when you need a return value in expressions, and print_r for debugging arrays and objects to see their internal structure.