Hello Monique,
CURL is an enviroment beeing installed on the server.
To avoid saying something wrong look by yourself at Wikipedia:
CURL - Wikipédia (french / very short text) and
CURL - Wikipedia, the free encyclopedia (english).
I still haven't used that and can't say something serious about it.
We will try to test the extension but that is also depending wether CURL is installable. I think the extension will be usable for us. Even if it's not installable on our server we can use the written code. But I don't want to decide anything now because I don't know the server and I'm no administrator.
What's about you? Do you think you can install the extension on your server?