Redirect standard output (Sobell, page 138) of echo to write a short mes- sage to a file and then use cat to display the contents of the file.

The echo builtin copies its arguments to standard output which, by default,

bash directs to the screen.

$ echo This message goes to standard output.

This message goes to standard output.



The cat utility sends the contents of a file specified by its argument to stan-

dard output.

$ echo hi there > hi.file
$ cat hi.file
hi there