You have text in a language you don't understand? Then select the text, hit an hotkey and the program will use online translation services (Google, Microsoft, ect.) to translate the text into a language you understand. This is the underlying idea. Unfortunately nothing seems to work here (under OS 10.10.3), and I found a review from 2013 in the AppleStore which says exactly the same, so apparently nothing has changed for the better in the last two years.
There are some useful settings in the Preferences that you are supposed to be able to toggle, such as "Window always on top", "Window Under Cursor", "Automatic Clipboard Translation", but none of these features are working. The window always stays on top; you have to click on the icon in the menubar to get it away. There is no automatic clipboard translation; instead, the text you select before you hit a shortkey, is just put into the clipboard. So if you are on a Russian web page and select some text, it's the Russian text that is put into your clipboard, not the translation. And, of course, Auto-detect language doesn't work properly either. [May 11, 2015]