Security and usage
NoScript takes the form of a toolbar in Firefox. It will display every site whose content is being both blocked and allowed for the current page being viewed, with options to either allow the blocked content or forbid the allowed content. Additional options can also be modified through this toolbar.
Site matching and whitelisting
For each site, the exact address, exact domain, or parent domain can be allowed, and subsequently, its content will be executed. By enabling a domain, (e.g. mozilla.org), all its subdomains are implicitly enabled (e.g. www.mozilla.org, addons.mozilla.org and so on) with every possible protocol (e.g. http and https). By enabling an address (protocol://host, e.g. http://www.mozilla.org, its subdirectories are enabled (e.g. http://www.mozilla.org/firefox and http://www.mozilla.org/thunderbird), but not its domain ancestors nor its siblings. Therefore, mozilla.org and addons.mozilla.org will not be automatically enabled.
Sites can also be blacklisted with NoScript. Blacklisting a site not only blocks it from executing scripted content, but also removes the option of allowing it to execute said content, unless it is removed from the blacklist.
NoScript is very popular, often topping Mozilla's most popular extension list
NoScript has also received numerous awards and recommendations, and is often recommended by the media. It has received critical acclaim, winning a PC world 2006 world class award.
NoScript is sometimes viewed as overkill, unnecessary, and tedious.