What is the difference between include and require in PHP?
The two functions are used to insert the content of a file into another PHP file before it is executed by the server. They are identical in every aspect, but they perform error handling in different ways. The include() function generates a warning (which does not halt execution) while the require() function generates a fatal error (which stops execution immediately).
If the file is not found by require(), it will cause a fatal error and halt the execution of the script. If the file is not found by include(), a warning will be issued, but execution will continue. require_once(), require(), include().