Keep files in sync between multiple computers

It's very easy to keep files in sync between multiple computers so colleagues, friends or team members can get the latest version whenever anyone changes a file. It works like following image:

Basically, what you need to do is to configure every computer to synchronize to the same folder on the FTP server. And, that's it, nothing special. Here is how it works:

1. A user changed a file
2. The file will be uploaded to the server first
3. Then, other user downloads the file from the server automatically
4. All users have the same and latest version now.