The output will be what you expect, it will echo Hello World onto the screen. You can also use echo to view the contents of a variable: As with most Linux commands, there's definitely more that we can ...

So, I just to perform a simple task. I want to echo the current date and time with some additional text to a file... basically clearing the file as I do so.<BR><BR ...

There are quite a few exit codes used on Linux systems, though no listing you can display when you’re feeling curious. In fact, you won’t see the numeric codes unless you specifically ask for them.