What is opinion?

Opinion is a tought, belief, judgement, viewpoint, or statement about something/someone or matters that commonly considered to be subjective. Not necessarily based on knowledge and fact. 

Opinions are subjective, that is what we think, but could be wrong. It is personal view. Different from argumentative which must be reasoned, logical ideas and give evidence-based. Arguments are objective. Argumentative is trying to persuade the reader of a spesific point of view.