What is the significance of setting 'allow_url_fopen' to On in PHP?

Setting 'allow_url_fopen' to On in PHP allows the use of functions like file_get_contents() to retrieve data from remote URLs. This can be useful for fetching external resources, but it also poses security risks if the remote server is not trusted. It is important to carefully validate and sanitize any user input before using functions that rely on 'allow_url_fopen'.

// Enable allow_url_fopen
ini_set('allow_url_fopen', 1);