PHP INTERVIEW QUESTIONS

    

 PHP INTERVIEW QUESTIONS

1. WHAT IS PHP?

PHP (Hypertext Preprocessor) is a server site scripting language designed for web development. It is widely used foe creating dynamic and interactive website. 

2 . Difference between echo and print?

echo is faster then print, can print multiple values,  No return value.

print slower, return 1 (true) prints on;y one value

echo "Hello", " World!";  // ✅ Works

print "Hello", " World!"; // ❌ Error

3. Difference between variable and constants? 

Both variables and constants store data, but they behave differently. 

variable can changeable constants cannot be modify after declaration 

variable have local and global scope, while constants are always global 

4. what are the different data type in PHP?

PHP has 8 primary data types 

    

Data Type	Example	Description
String	"Hello"	Sequence of characters
Integer	10	Whole number
Float	10.5	Decimal number
Boolean	true / false	Logical values
Array	[1, 2, 3]	Collection of values
Object	new ClassName()	Instance of a class
NULL	NULL	No value
Resource	mysqli_connect()	External resource (e.g., database)

5. What is difference between NULL and 0?

   Both NULL and 0 represent "nothing",  but they are different

    . NULL -:  no value assigned  

    . 0 -:  Numeric value zero.

6. Difference between == and === ?

    ==  checks value only 

    === checks  value and data type 

var_dump(2 == "2");  // true (only checks value)

var_dump(2 === "2"); // false (checks value & type)

 

7. What is function is PHP?

    A function is a block of code that can be reused.

    function greet() {

        return "Hello, World!";

  }

  echo greet();

8. How do you return a value for a function?

    To using a return keyword. 

function add($a, $b) {

    return $a + $b;

}

echo add(5, 3); // 8