Backed up HD to tar., ZIP, g-zip file stuck on shell prompt

I followed a tutorial online about backing up youre hard drive to to a compressed file and then saveing that file on an external Harddrive.
I enterd (cd-) into the cmmnd i cant remember the exact thing i entered, i was viewing that great tutorial on my computer wich is now stuck on the prompt window...

Ill send some pics of the code or commands, its a linux mint 17.2 rafaela