The English words affect and effect are often confused by native speakers – don’t let their mistakes affect your English.
Affect is a verb with several different meanings.
1. To have an influence on, contribute to a change in
2. To touch, move; to act on the emotions of
3. To simulate
In psychology, affect is a noun which refers to a "feeling" or "emotion":
Effect is most commonly used as a noun, and has three meanings:
1. Result, something brought about by someone or something
2. Something that gives the impression/sense of something else
3. Effects can refer to belongings.
As a verb, to effect means "to bring about, lead to a result"
The Bottom Line
The confusion between affect and effect comes out of the fact that affecting something leads to an effect. The two questions "How were you affected?" and "What was the effect on you?" mean almost exactly the same thing.
When you want to use one of these words as a noun, the one you want is probably effect. When you want a verb, most of the time you want affect. Effect is used as a verb only when it has a direct object and only when you mean "to bring about, lead to."
The difference between to affect and to effect can be seen clearly here:
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