Hidden Files
 

how can i make a file or folder hidden and then how can i make visible again for linux red hat 9.0 ?

Files and directories bwginning with a . (dot) are hidden. It's easy to find hidden files though with the -a argument to ls.

The dot before the file name is what hides it. So if you have a file called test.txt, you can hide it......
mv test.txt .test.txt

or to unhide the file...
mv .test.txt test.txt

Edit: Sorry BT, Our posts crossed on the wire. :)

What do you mean "make a file or folder hidden"? Generally, any file or folder name that starts with a dot (.) in *nix is considered a hidden file. At the command line, and ls -a will list all files including hidden ones. So, renaming "file" to ".file" will make it hidden. In GNOME, you can configure whether or not to show hidden files. In a nautilus window (file manager), click Edit > Preferences and check "Show hidden and backup files." I don't know about KDE, but I know you can configure this.

Hth.
Josh

Try View
 

I think it is under VIEW, it says hidden files, and when you click on it, you get a check mark in front of it, and Konqueror shows the hidden files.