Do not confuse the words affect, effect, and impact, each of which can be used both as a verb and as a noun. Avoid incorrectly using impact as a verb in place of affect or as a noun in place of effect.
Affect as a verb means "to influence."
Affect as a noun has a specialized meaning in medicine and psychology, referring to moods and feeling as distinct from thoughts or knowledge.
Effect as a verb means "to bring about, to produce," or to "accomplish something."
Effect as a noun means "result."
Impact as a verb means "strike with a blow" or "to pack firmly together."
Impact as a noun means "a collision."
Do not use impact as a verb in place of "to affect", do not use impact as a noun in place of "effect."
impact also has the meaning of a marked effect or influence: The Beatles had a major impact on the pop music world.
effect has several meanings :
1 a change which is a result or consequence of an action or other cause. The discovery of penicillin had a major effect on medical treatments 2 the state of being or becoming operative. The Act will take effect next month. 3 the extent to which something succeeds or is operative: wind power can be used to great effect.
4 (effects) personal belongings.
5 (effects) the lighting, sound, or scenery used in a play or film. 6Physics a physical phenomenon, typically named after its discoverer.