yii:::t method usage

i have studied loads of forums but can anyone please help me understand that how to use yii::t and and what is the significance of first parameter category in the method (yii::t) please explain giving some exmaple

maybe this helps you (use it with google translator)

http://blog.mbischof.de/yii-message-translation

unfortunately, the german site is down

here’s a wiki article: use-shortcut-functions-to-reduce-typing