I have read master morality vs slave morality through youtube and net. Every one has different interpretation. Can some one summarize and explain what Nietzsche really tried to say ?
I guess that Master morality, in Nietzsche's view, arises from the "noble and powerful". It's a morality that values strength, courage, power, and freedom. It's a 'yes-saying' attitude that affirms life and the self. It's about being proactive, shaping the world according to one's will.
On the other hand, Nietzsche saw slave morality as a reaction to master morality. It emerged among the weak and oppressed, those who lacked the power to impose their will. Instead of valuing power and strength, slave morality values things like humility, empathy, and kindness. It's a 'no-saying' attitude, a kind of resentment against life's hardships and those who seem to thrive in spite of them.
Now, Nietzsche wasn't advocating for everyone to become 'masters' in the crude sense. He saw the dangers of unchecked power and the potential for tyranny. But he was deeply concerned about the risk of becoming too entrenched in a slave morality mindset, of becoming resentful of life and its challenges, of failing to affirm one's own existence and potential.
First, a point worth considering... Nietzsche believed that all established (traditional, doctrinal, etc) morality was flawed. Morality in his work is always something that must be transcended because it limits the application of will, which must (for the over-man) respond to a more authentic and esoteric form of morals. So when Nietzsche makes a distinction between Master and Slave moralities, he's not trying to promote one or the other. He is analyzing them as a medical doctor would do a differential diagnosis between correlated pathologies.
'Master' morality, in Nietzsche's view, is effectively a form of rampant selfish individualism. The will to power is twisted into an obsession with dominance, where the indicators of moral value are victory, wealth, virility, social esteem, and any recognized outcome of physical or mental strength. Winning is everything and losing is unthinkable, because winning/losing is what determines moral worth. Donald Trump is maybe the premier example of someone instilled with Master morality ("We're going to have so much winning...!"), but it's a common enough moral worldview that he attracts large numbers of people who see his overblown 'masterism' reflected in their own self-image.
'Slave' morality is a form of (not quite the right word, but...) communalism. The will to power is twisted away from dominance (which a 'slave' cannot hope to achieve) and towards virtuousness, where the indicators of moral value are kindness, selflessness, restraint, humility, cooperativeness, etc. Moral worth is determined by one's 'Goodness'. Mother Teresa is probably the iconic example of this, but it's a bit difficult to pick out prominent examples because such people don't tend to make a show of things.
The will to power has a distinct social aspect to it. The 'master' tries to empower himself by getting others to respect his ruthlessness and strength; the 'slave' tries to empower himself by getting others to respect his goodness and incorruptibility. The over-man, by contrast (and here I speculate a bit), empowers himself by getting others to respect his absolute authenticity, irrespective of dominance or coherence to virtue.