^
Ssh is browsing your iPod files from your computer, you can copy, delete paste... edit and stuff, just like you can with my computer on your computer
(look up a tutorial on the internet, how to ssh into your ipod, sites like modmyi are trustable, you can also look it up on youtube, winscp is the client)
SHSH's name is maybe similar to ssh, but extremely different
I'm really sorry, but shsh is quite hard to explain (and most of all, a big story
and I'm quite lazy atm)
What you have to do is go to Cydia, and then click make my/your life easier on top (iirc)
This enables you to downgrade firmwares that are not being signed by apple anymore.
Look up a tutorial for this too, downgrading is useful when tere is no jailbreak available for the newest firmware at that moment.
Or when apple f*cks something up, you probably want to downgrade