Every webdeveloper has probably at some point wondered which technologies a particular site is using. Sure, you could browse the source of a page to find any hints on for instance what cms is being used. Or you could inspect the response headers to see what version of php is used.

Instead of hunting down those clues yourself, you could use the Wappalyzer plugin. Once installed it shows an extra icon in your browser. It indicates what sort of framework or cms is used. Clicking on the icon reveals even more info such as which JavaScript libraries are embedded on the site. It's a great tool.