How can folder permissions affect PHP scripts that involve file uploads?

Folder permissions can affect PHP scripts that involve file uploads by restricting the ability of the script to write to the designated upload directory. To solve this issue, ensure that the folder where files are uploaded has the correct permissions set to allow the PHP script to write to it. This can be done by setting the folder permissions to 755 or 777, depending on the security requirements of the server.

// Set the correct folder permissions for file uploads
chmod("uploads", 0755);