What are some common methods for loading external files onto a server in PHP?

One common method for loading external files onto a server in PHP is to use the `file_get_contents()` function. This function allows you to retrieve the contents of a file and store it in a variable for further processing. Another method is to use the `fopen()` function to open a file and then read its contents using `fread()`. Additionally, you can use cURL to download files from a remote server and save them locally on your server.

// Using file_get_contents
$file_contents = file_get_contents('https://www.example.com/file.txt');

// Using fopen and fread
$file = fopen('https://www.example.com/file.txt', 'r');
$file_contents = fread($file, filesize('https://www.example.com/file.txt'));
fclose($file);

// Using cURL
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, 'https://www.example.com/file.txt');
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
$file_contents = curl_exec($ch);
curl_close($ch);