PHP Beginner Questions Interview Preparation

 Level        Type

Beginner                Basics (syntax, variables, data types, operators, loops, functions)


1. What is PHP?
➤ PHP is a server-side scripting language used to create dynamic web pages.

2. How to declare a variable in PHP?
➤ Using $

$name = "Lakshmi";

3. What are PHP data types?
➤PHP data types are like Integer, Float, String, Boolean, Array, Object, NULL, and Resource — used to define what kind of data a variable stores.
➤You can check a variable's data type using var_dump($variable);
➤ String, Integer, Float, Boolean, Array, Object, NULL.

4. How do you write comments in PHP?
➤ Single-line: //, multi-line: /* comment */

5. What is the difference between echo and print?
➤ Both echo and print are used to display output in PHP
➤  echo can output multiple values, faster. print returns 1, usable in expressions.

6. How to write a function in PHP?
➤ A function in PHP is a reusable block of code that performs a specific task and is defined using the function keyword.
➤ In PHP, a function is created using the function keyword, followed by a function name, parentheses (), and curly braces {} containing the code to run

function greet($name) {
    return "Hello $name";
}

7. What are constants?
➤ Defined using define(), values that don’t change.

8. What is a loop?
➤ Used to execute code repeatedly: for, while, foreach, do...while

9. What is the difference between == and ===?
➤ == checks only value, === checks value and data type both .
👉 Always use === when you want strict comparison (especially when working with login/authentication, form validations,

10. How to include a file in PHP?
➤ include 'file.php'; or require 'file.php';

11.What is the use of isset()?
➤ isset() Checks if a variable is set and not null.

12. What is empty()?
➤ It's checks is variable is empty or not. Returns true if a variable is empty.

13. What are superglobals in PHP?
➤ Built-in variables: $_GET, $_POST, $_SESSION, $_FILES, etc.

14. What is the difference between $_GET and $_POST?
➤ GET: data in URL, visible; POST: secure, in body.
  • $_GET sends data via URL, is visible, less secure, and good for search or pagination.
  • $_POST sends data hidden in the request body, is more secure, and ideal for forms like login or registration.
15. How to create an array?
➤ An array in PHP is a variable that can hold multiple values at once.
You can create it using array() or short syntax [].

$arr = array("one", "two", "three");

16 . What is the die() function?
➤ Terminates script execution and shows an error message.

17. How do you concatenate strings in PHP?
➤ Using the dot (.) operator:
$full = $first . $last;

18. What are magic constants?
➤Magic constants in PHP are special predefined constants that give information about the file, line, function, class, or method dynamically. They are very useful for debugging and meta-programming.
  • __LINE__
  • __FILE__
  • __DIR__
  • __FUNCTION__
  • __CLASS__
  • __METHOD__
  • __NAMESPACE__
They start and end with double underscores (__) and provide static info.

19. What is var_dump() used for?
➤ Displays detailed variable info (type + value).

20.What is a NULL value in PHP?
➤ A variable with no value assigned.

21. What is a PHP array?
➤ An array in PHP is a special variable that can store multiple values under one name

22. What is the use of the $_POST variable in PHP?
➤$_POST is used to get data from an HTML form when the form's method is POST.

23. What are the different types of loops in PHP?
➤PHP supports for, while, do...while, and foreach loops to repeat code blocks based on conditions or array data.

24. What is the purpose of the break statement in PHP?
➤ break is used to terminate a loop or switch case early when a certain condition is met.

25. How do you connect to a MySQL database in PHP?
➤ In PHP, you can connect to MySQL using mysqli_connect() by providing server, username, password, and database name.

26. How do you fetch data from a MySQL database in PHP?
➤ We fetch data using mysqli_query() to run the SQL SELECT statement, and mysqli_fetch_assoc() to get rows as an associative array.

27. What is a PHP session?
➤ A session stores user data on the server across multiple pages using a unique session ID

28. What is the use of the $_GET variable in PHP?
➤ $_GET is used to collect form data or information passed via the URL in PHP.

29. What are superglobals in PHP?
➤ Superglobals are special global arrays in PHP used to access data like form inputs, server info, sessions, and cookies from anywhere in the script.
  • $_GET — Data from URL parameters.
  • $_POST — Data from HTML forms (POST method).
  • $_REQUEST — Data from GET, POST, or COOKIE.
  • $_SESSION — Data stored in user session.
  • $_COOKIE — Data stored in cookies.
  • $_FILES — Information about uploaded files.
  • $_SERVER — Server and execution environment info.
  • $_ENV — Environment variables.
  • $_GLOBALS — Access all global variables.
30. How do you handle file uploads in PHP?
➤ We use $_FILES to collect the uploaded file and move_uploaded_file() to save it to the server.











































































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