Quotes About Filenames

To see an input stream at work, enter cat (with no filenames) and press ENTER. This time, you won't get your shell prompt back because cat is still running. Now type anything and press ENTER at the end of each line. The cat command repeats any line that you type. Once you're sufficiently bored, press CTRL-D on an empty line to terminate cat and return to the shell prompt.

at* expands to all filenames that start with at. *at expands to all filenames that end with at. *at* expands to all filenames that contain at.