What's the difference between "affect" and "effect"?
Th meaning of "affect" is cause somebody or something to change in a particular way.
effect is noun of affect , means a change that is caused by something.
another meaning of effect is :to cause something to happen

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"Effect" is rarely used as a verb nowadays (although it is both a noun and verb); likewise, "affect" is rarely used as a noun (although it is both a noun and verb).  The definition you used in your question is a good one, and will serve for 99% of the time.

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Affect is a verb where as effect is noun.

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These are words that even native English speakers have difficulty with.  Generally speaking, "affect" is used as a verb and "effect" is a noun, but there are a number of exceptions.

I highly recommend http://grammar.quickanddirtytips.com/affect-versus-effect.aspx for a very good lesson on their uses.