To send the output from a command such as "cat" to a file, you can use either '>' or '>>'. For example cat jabber wocky > poem would put the contents of "jabber" and "wocky", one after the other, in a new file called "poem". You can think of the '>' as an arrow pointing to where you want the output to go. In the above example, if "poem" already exists, then it will be over-written (i.e. it will be deleted before it is recreated). Sometimes that is what you want, but often you will want to keep the previous contents of a file and simply append to it (add to the end of it). This can be accomplished by using '>>' rather than '>'. Click the right arrow.