How to set up cd - on ubuntu
 

i was following an online guide to install a tar.gz file and it said to type in "cd -" in the terminal so i did but the terminal said i didnt have it set up

if anyone can please help me set it up it would help a lot - thanx in advance

Are you sure it didn't mean
Because that would make more sense to me..with 'su -' you become superuser (dash ensures the root's environment is in use, not the user's). 'cd' is used to change working directory.

On my machine, "cd -" toggles between the current directory and the last one I was in. Handy tool, but I can't tell how it relates to installing a tar.gz

To "install" a tar.gz:
tar xzvf filename
open the folder that is created
find the README file for further instructions (it depends on what the thing is that you are installing)