Downloading an application from the web?

Let me post a lil' outline.

* Suppose I've a program, it's casually acts as an updater. ( It's not updater at the moment, it is just a redirection program. )

* I've a web domain and a facility for an year of host. I want the program to download the files and replace the old files.

* I also would like to have the program to check for updates right after runnin' the program, if there ain't any file in the specific file in "public_html\123\updates\.."

_Would someone like to tut. me or teach me how to?

_Example would be appreciated.

*Thank Q vm.