ESP8266 upload files to website

Hello, I would like to use ESP 8266 to send/upload files of different format (saved on SDCard by an arduino) to an online website server. (Like streaming data to a site).
My challenge would be that: the esp 8266 would have to act as the client side, and the website as the server.

If this is possible, kindly explain possibility with some code. PHP on the server side will be ok.

Thanks

see if it is possible to FTP