How to only backup changed files

Hi,friends

I use winscp3 to backup my data to the server. It contained large dataset and files. When I coping all of them, it always take a long time. How can I only over-write the changed files based on changed time. If one file is not changed since last backup, then skip over-writing this file.

I would highly appreciate your help.

Jing

That's what synchronization is good for.