PHP Programmer Interview Question

What is the difference between include() and require() functions in PHP, and when would you use each one?

In PHP, both include() and require() functions are used to include and evaluate the specified file in the current script. The main difference between them is how they handle errors.

With the include() function, if the specified file is not found, a warning is issued, but the script continues to execute. On the other hand, the require() function will generate a fatal error and stop the script execution if the specified file is not found.

You would typically use include() when the included file is not crucial for the script to run successfully, such as including a file with optional content like a sidebar or footer. On the other hand, require() should be used when the included file is essential for the script to work correctly, such as including a configuration file or a database connection script.