PHP Industry-Specific Questions

1. What are the differences between `include`, `require`, `include_once`, and `require_once` in PHP, and when would you use each?

2. Can you explain how PHP handles sessions and cookies? What are the differences between them?

3. Describe the various ways to handle errors and exceptions in PHP. What is the difference between the `try-catch` block and using custom error handlers?

4. How can you prevent SQL injection attacks in PHP applications? Provide examples of safe coding practices.

5. What are PHP traits, and how do they differ from classes and interfaces? When would you consider using traits in your application?

6. Explain the use of the `Composer` dependency manager in PHP. How does it help to manage project dependencies effectively?

7. Discuss the concept of namespacing in PHP. What advantages does it provide, particularly in large applications?

8. How does PHP’s garbage collection work? Describe how it manages memory, particularly with reference counting and cyclic references.

9. In what scenarios would you use the `PDO` extension instead of the `mysqli` extension for database interaction in PHP?

10. In object-oriented PHP, what are the differences between abstract classes and interfaces? When would you use one over the other?