When using terminal ...

I will look for a file but then it says some thing like
.: ..: filename argument required and something else.?
what does it mean?

Does it actually say "something else", or is there just something else you can't remember? It'd would help to be more specific if the answer is the latter.

no it does not say "something else" but i am sure it says file argument required and then :. or .: but there are dots...a few..
sorry i am not much help, i will try it again and write it word for word.
Thank you!

ohoh..it says."is a directory"

What exactly are you typing in?

Under UNIX . and .. represent the current directory and the parent directory respectively. Ancient UNIX secrets, really. So to refer to a file in the current directory, you could use ./whateverthefileis.txt for a file that's where you are currently positioned, or ../whateverthefiles.txt for a file that's up in the directory above you.