Freedom of speech means having the liberty to say, express or publically announces any thoughts, ideas and opinions as long as they are not harassing or accusative in nature. The belief that every living being has an equal right to live, act, think and behave in whatever they find best, leads us to have freedom of expression and speech. For example, a physicist has the equal right to believe and say there is no super natural existence beyond our knowledge, as does the religious believer to believe in God. Similarly, people can have their own opinions about a government, artwork, famous personalities, nation, religion and culture. As long as they are not harassing or accusing someone else, it is fine to say what you believe.
However, this is the theoretical definition of freedom of speech, which is not exactly similar to the realistic approach. Freedom of speech is more of an ethical and psychological approach than a political. Even though you have the right to say what you feel but you should not be saying insane stuff about someone’s belief system that he or she is emotionally affiliated to. This does not only hurt them but can also lead to worse case scenarios. There have been murders, violence and criminal acts in response to what someone though were a mere right to speak.