cURL or file_get_contents ???

I'm studying for joomdle presentation to MoodleMoot

I did not understand the difference between the connection protocol via file_get_contents and cURL

I understand that the protocol cURL must be present on the web server, I do not understand what is the difference from the functional point of view.

What will change for the user if you activate one or the other protocol?

Thanks

It is just the transport method used.

The 2 are available, because there are servers that only have one of them.
The funcionality is the same,