concept

As-Salamu `alaykum. Please enlighten me on the concept of kufr in Islam. What does kufr mean? Are we allowed to label anyone kafir without any justification? Are there various levels or forms of kufr? Jazakum Allah Kharian!

As-Salamu `alaykum wa Rahmatu Allah wa Barakatuh. I’d like to know the meaning of Fatwa and its significance. Thanks in advance for answering my question.