How can server overloading affect PHP scripts and lead to errors like "Too many open files in system"?

Server overloading can lead to PHP scripts opening too many files at once, causing the system to reach its limit and resulting in errors like "Too many open files in system." To solve this issue, you can increase the maximum number of open files allowed by the system or optimize your PHP scripts to close files properly after use.

// Increase the maximum number of open files allowed by the system
ulimit -n 2048;