In other words, this site is pretty safe...
This is for jailbroken iOS device only. Users who didn't jailbreak can't install the required software on their device.
In cydia install the openssh package. Then restart your iOS device.
Note that in older devices you may want to temporarily turn off the autolock from the General settings of the phone (Settings -> General -> Autolock).
To ssh to the device you will need to know its ip address. To check the ip address, go to "Settings -> Wi-Fi" and click on your wifi network name.
Once you know the address, you can connect using the user "root" with password "alpine" (without the quotes).
The first time you connect to your device it takes arround 15 seconds for the keys to be generated.
It is strongly recommanded to change the default password.
To do so you can follow the instruction in the following wiki post: How do I change my iPhone, iPod or iPad root password ?
On mac, if you just want to transfer files, you can use cyberduck which is an excellent free software. Note that in cyberduck the type of connection you want to use is SFTP (ftp over SSH).