• File - file is your friend. It can help you determine what type of file something is. Whcich could be helpful for determining *couch*decodingtools*cough* stuff.
• apropos - It can help find the manual pages for some of the different tools that you will need to use. It might be worth paying attention to file names.

-At the start you can only access ascii.512

-Don't forget that file allows to see any extra information about the file.

File can be helpful for determining a file type and apropos for finding a particular command to use on such file types. Another thing to pay attention to is the actual names of the files.