Why South Indians hate North indians and vice versa?

South Indians do not hate North Indians and North Indians do not hate South Indians. People hate each other. Hatred is born when we make a separation saying that I am a South Indian and you are a North Indian. Hatred is born when we make a separation on any basis, be it caste, religion, intelligence, voice, language, size of body, color of skin, etc. Remember, if you are in the hospital and need some blood and I have the same blood group, my blood can save your life, irrespective of whether I'm a South Indian or a North Indian or however distinct I am from you. Language, culture, etc are simply connected to the surroundings. But We share the same feelings. Pain, Pleasure, Fear, etc are all the same. So PLEASE stop distinguishing between people and let us love each other!

Cant Answer the question since I am from western part of India  -- And yes I thought we all are only Indians first

I don't agree with you. That seeming hatred is because of unfamiliarity. We build our presumptions based on what we see on media and what we read about the other. 80% or more of the people who have had the chance to mingle with the other will say that the other is just like them or at least highly acceptable. Request you to not create a non existent hatred.

I don't think they hate south Indians but if I can imagine why they hate south Indians : first reason could be their skin color and the second one would be language difference(most of the north Indian languages sounds same or they speak hindi)

People with inferiority complexes resort to hate. That is why some South Indians hate North Indians and some North- Indians hate South Indians. Honourable people want to make their fellow citizens at home all the time. Nothing wrong with Hindi. Most South Indians would happily speak it if the politicians stop spewing venom for their petty illiterate electorate to turn advantageous. Lowly people respond the best to words like tradition, culture, religion, caste etc. Educated ones require talks of fiscal policies, infrastructure and job creation. You would be surprised how a tiny number of culture goondas hold the whole region hostage and how most people are basically nice. It is not stupid to make Hindi our national language. It has an almost Anglo script and makes it easier for a person to be phonetically closer  to all other anglo scripts which means all european languages. Written language is not enough and one needs to be phonetically sharp to be cosmopolitan. India does not have enough for everyone. People need to be able to communicate on a global scale to do business. Hindi makes it easier although a lot of people may not be able to take much of an advantage as Hindi basically is not a regional language in any part of northern India either. Sanskrit is another choice but then there is a cast barrier and a lot of people may not agree to use it just as a lot of people may not agree to let others use it. Ya, India is a strange place. Big news.

No one sensible hates anyone else without a valid reason. However, being a North Indian I haven't had pleasant impressions of the people from South,.They have a different way of looking at things, are insecure somehow perhaps, boast of how well-off their states are, don't accept where they lag compared to the North (for example all people in North will totally admit HDI of Southern states is better generally). They sometimes think speaking in Hindi is something being pushed up on them. The fact is that each  and every state in the North AND south- Punjab, Rajasthan, Kerala, Uttarakhand, Assam, Haryana, UP, Bihar, Maharashtra, Tamil Nadu and so on has its own language/dialect, yet there is a kind of unity created by Hindi in the North while Southern states stick to their own language. If all were like them, no one would want to learn Hindi even in the North.Also, they made be super educated but are more orthodox in thinking or religion I think, may be I am completely wrong, but there is something about their way of looking at things and making arguments that is out of the world for me. PS.  I know some greatttt SOuth Indian friends! :)

Actually the case is from both side. The reason why North people hate SOME south people is some south people don't mix with north people, they live in their own state groups as per I have seen. And the reason why South People hates north people should be asked to south people only...

No one hates north indians in south. This General presumption by a north indian. It is just that some north indians which irritate us to the core which make us have a general bad opinion about them. Imagine if you are being called idly dosa, black lungi wearing indian, conservative and top of all most abuse our languages. So will you like such person??? Despite all this if you behave and respect them in southern state and dont talk shit about them on their faces southies will never hate you

We North Indians have deserved this behaviour that is why. The story describes my statement: 1982-83: Every class has a topper a nerdy fellow, who is involved only in Books and Knowledge, who bothers least about what is going in and out of the class and school,  the one for whom everyone is sure he will do something greeeaaat! Such was 'Gupta'. And Gupta proved his value right, selected in the top NIT at that time, NIT-Tiruchirappalli or NIT Trichy as we call it. Scared to leave his hometown for the first time, and going into an absolutely alien land as have heard of the South India! resided by Dark-skinned English men. So here he was, and as soon as possible he found some more like him there. There was a huge groupism and surprisingly it was like the British Rule in India long ago. The Northies used to rule the Southies, because the North were all united, and because of the fact that the Southies were extremely scared of us and were so gullible and innocent like child, but the wolves moved in a pack of 6 at-least and got their chores done by their Southern counterparts. Its not that, there was not any retaliation but the fear of the fair-skinned  made sure that only a few voices rose against them who were beaten, and Gupta was the one beating them, obviously with some more Northies. The same Gupta who once called his classmates as 'aap', who now abused them with words even his notorious friends have not heard of. And he enjoyed his stay at the NIT, he says he apologised on the last day but what then! He accepts that those four years were the best of his life: 1984-88.