From this [commandlinefu post](http://www.commandlinefu.com/commands/view/6856/diff-remote-webpages-using-wget):

```
$ diff <(wget -q -O - URL1) <(wget -q -O - URL2)

```

Seems like multiple standard inputs but---if I remember my Linux Porgramming course correctly---this can't be it. I thought that, by definition, standard input was one stream.

Perhaps this has zilch to do with stdin? Can someone explain this to me; maybe provide links to documentation.

**Bonus:** How would a script handle these multiple streams? If someone could provide a Python or Perl example, that would be very helpful.