How can developers prevent unauthorized access to PHP files on a web server using .htaccess files?

Developers can prevent unauthorized access to PHP files on a web server using .htaccess files by restricting access to specific IP addresses or using password protection. This can help secure sensitive information and prevent unauthorized users from accessing and potentially manipulating PHP files. ```apache <FilesMatch "\.php$"> Order deny,allow Deny from all Allow from 192.168.1.1 </FilesMatch> ```