Well they both are identical when it comes to physical use but the only difference is error reporting. If include() fails then a standard error will be displayed and the page will continue loading however, if require() fails then the entire script fails and the entire page comes to a stop with the error message.
Hi this is nathen,
The include() function takes all the text in a specified file and copies it into the file that uses the include function.
The require() function is identical to include(), except that it handles errors differently.
The include() function generates a warning (but the script will continue execution) while the require() function generates a fatal error (and the script execution will stop after the error).