FTP setting within Dolphin

Can anyone tell me what exactly the FTP settings are within admin - settings/advanced/other

Does this create an ftp folder that all users can upload into?

If so, where is the 'link' to this on display within Dolphin front end?

I think it's the FTP settings for your server. It's so you can upload and install modules automatically. I've never used it but I've heard it doesn't work as intended.