I want to add to a server the ability to recieve uploaded files (eventually this server will copy the uploaded file to another location on the network).

I searched online and ran into jQuery for ASP.NET.
I just don't understand what's the use in it and how is it better. Why not using the usual .NET C# classes and functions, such as FileUpload.SaveAs and then copy the file?
Am I missing something here?

Thanks.