when i open terminal
 

hi knudfl....
when i open the terminal this line appear

bash: /usr/local/lib: is a directory
dina@dina-Satellite-L635:~$

without wirtting and command????

Try
It looks like one of these has an error in it

yea, it sounds like there's an eror in .bashrc
you can use cat to find the error then edit the file in vim/emacs/

It's somewhere "cat /usr/local/lib" line is mentioned in your shell initialization file, which actually gets sourced when you login. Since /usr/local/lib is not a file, but a directory, thus system shows you this message. So do try this:
more .bashrc | grep "/usr/local/lib"
Or,
more .bash_profile | grep "/usr/local/lib"
If it gives some output, then edit the corresponding file using vi or vim & either comment the line that contain this line, or replace "cat /usr/local/lib" with "cd /usr/local/lib". Hope it will help you!

Is that functionally different from cat .bashrc | grep "/usr/local/lib" or grep "/usr/local/lib" .bashrc ?

BTW .bashrc could, more robustly, be ~/.bashrc

No! But I find "more" more flexible than cat.

@dina: You can simply try with:
grep "/usr/local/lib" ~/.bashrc
Or
grep "/usr/local/lib" ~/.bash_profile