Web sites that accept postings from the public, like this wiki, are often abused by spammers who use automated tools to post their links to many sites. While these spam links can be removed, they are a significant nuisance.
Sometimes, such as when registering as a new using or adding new web links to a page, the wiki may ask you for "the output of a command". You must run that command on a UNIX operating system to continue. Since offshore human spammers use Windows computers, this task is difficult for them.
If you do not have a UNIX operating system available (such as Linux or Mac OS X), you can use JSLinux from your browser.
Hit the "back" button in your browser to return to the page editor or registration screen.