Free speech:  Free speech is the right to speak whatever someone want to speak. That means there is no fear to speak .There is no fear of discussing or giving any speech.

Hate speech: Hate speech means creates problem or create argument between people by your says,writing,behaviour etc. It contains hatred information/data about others.  

Offensive speech: Offensive speech makes controversy. It creates so many points between peoples or countrie. If someone's speech goes against law it will be called offensive.