What is a Hater?

It has come to my attention that everybody thinks they have a "Hater" but what is a "Hater" ? I looked the word up and it say's " To dislike intensely or passionately". Everybody seem's to say that they hate haters but doesn't that infact make you a "Hater" ? If somebody states their opinion and say's what they think does that make them a hater? If you have on shoes and I think that they are ugly and I tell you does that make me a hater? If being a hater is just being jelous then aren't we all haters? I know for a fact that we have all been jeouls of someone at one point in time. To me hater is just another pointless word to make us all feel important.