1. What is PHP?
PHP is a server-side scripting language that is used to develop dynamic web applications. It stands for Hypertext Preprocessor.

2. What is the difference between PHP and HTML?
PHP is a server-side scripting language that is used to generate dynamic web pages, while HTML is a markup language used to structure and format content on a web page.

3. Explain the difference between GET and POST methods.
GET and POST are HTTP methods used to send data between a client and a server. GET sends data as part of the URL, while POST sends data in the request body. GET is less secure and has a limit on the amount of data that can be sent, while POST is more secure and has no limit on data size.

4. What is the use of echo in PHP?
The echo statement is used to output text or HTML content to the browser. It can be used to display variables, HTML tags, or any other string of text.

5. What are PHP sessions?
PHP sessions allow you to store and retrieve data across multiple pages for a specific user. They make it possible to remember information, such as a user’s login credentials, throughout their browsing session.

6. What is the difference between require and include?
Both require and include are used to include external files in PHP. The main difference is that require will cause a fatal error if the file cannot be found, while include will only issue a warning and continue execution.

7. How can you prevent SQL injection in PHP?
To prevent SQL injection, you should always use prepared statements or parameterized queries when executing SQL queries in PHP. These methods ensure that user input is treated as data and not as part of the SQL query.

8. What is the use of the “==” operator in PHP?
The “==” operator in PHP is used to compare two values for equality. It checks if the values are equal, regardless of their data types. For example, “5” == 5 would return true.

9. What is a superglobal in PHP?
Superglobals in PHP are predefined variables that are available in all scopes throughout a script. Some examples of sup

Question 1: What are the new features in PHP 7?
Answer: PHP 7 comes with several new features including better performance, scalar type declarations, return type declarations, anonymous classes, and the spaceship operator.

Question 2: Explain the concept of inheritance in PHP.
Answer: Inheritance is a feature in PHP that allows a class to inherit properties and methods from another class. The derived class (child class) can access the properties and methods of the base class (parent class).

Question 3: How can you prevent SQL injection in PHP?
Answer: To prevent SQL injection in PHP, you should use prepared statements or parameterized queries. These methods ensure that user inputs are treated as data rather than executable SQL code.

Question 4: What is the difference between static and dynamic method in PHP?
Answer: Static methods are associated with the class itself and can be called without instantiating an object. Dynamic methods belong to an instance of a class and can only be called on objects.

Question 5: How do you handle errors and exceptions in PHP?
Answer: PHP provides error handling mechanisms such as error_reporting, display_errors, and error_log directives in the php.ini file. Additionally, exceptions can be used to catch and handle specific errors.

Question 6: What is the purpose of the autoloader in PHP?
Answer: The autoloader in PHP is used to automatically load classes when they are needed. It eliminates the need for manually including class files using require or include statements.

Question 7: How can you create a secure PHP session?
Answer: To create a secure PHP session, you should use session_regenerate_id to regenerate the session ID on each request, set the session cookie parameters to be secure and HTTP-only, and validate user inputs to prevent session hijacking.

Question 8: What is the difference between GET and POST methods in PHP?
Answer: GET and POST are two methods for sending data from a client to a server in PHP. GET appends the data to the URL and is visible in the browser’s address bar, while POST sends the data in the HTTP request body and is not visible.

Question 9: What is the difference between require and include in PHP?
Answer: Both require and include are used to include external PHP files. The main difference is that require will produce a fatal error if the file cannot be included, while include will only produce a warning.

Question 10: How can you prevent session fixation in PHP?
Answer: To prevent session fixation in PHP, you should regenerate the session ID after successful login and use session_regenerate_id to create a new session ID on each request.

Question 11: Explain the difference between echo and print in PHP.
Answer: echo and print are used to output strings in PHP. The main difference is that echo has no return value and can handle multiple arguments, while print returns 1 and can only handle one argument.

Question 12: How can you optimize PHP performance?
Answer: PHP performance can be improved by using opcode caching, enabling gzip compression, minimizing database queries, optimizing SQL queries, using appropriate data structures, and enabling browser caching.

Question 13: How can you upload files in PHP?
Answer: Files can be uploaded in PHP using the $_FILES superglobal. The uploaded file is stored in a temporary location, and it can be moved to a permanent location using the move_uploaded_file function.

Question 14: What is the purpose of the final keyword in PHP?
Answer: The final keyword in PHP is used to prevent a class from being extended. If a class is marked as final, it cannot be subclassed.

Question 15: What is the purpose of the __construct method in PHP?
Answer: The __construct method is a special method in PHP classes that is automatically called when an object is created. It is used to initialize the object’s properties and perform any necessary setup.

Question 16: How can you handle file downloads in PHP?
Answer: File downloads in PHP can be handled by setting the appropriate headers using the header function and reading the file contents using the readfile function.

Question 17: What is the purpose of the SPL (Standard PHP Library) in PHP?
Answer: The SPL in PHP provides a set of interfaces and classes to help with common programming tasks such as data structures, error handling, iterators, and more.

Question 18: How can you prevent cross-site scripting (XSS) attacks in PHP?
Answer: To prevent XSS attacks in PHP, you should sanitize user inputs using functions like htmlspecialchars when displaying them, properly encode or filter user inputs when saving them to the database, and use output escaping when echoing dynamic content.

Question 19: What is the purpose of namespaces in PHP?
Answer: Namespaces in PHP are used to organize code into logical groups and avoid naming conflicts. They provide a way to encapsulate and group related classes, interfaces, functions, and constants.

Question 20: How can you implement a singleton pattern in PHP?
Answer: A singleton pattern in PHP can be implemented by making the class constructor private, providing a static method to get the instance of the class, and storing the instance in a static variable.