Affect vs Effect
Most generally, affect is used as a verb and effect is used as a noun. When something ‘affects’ something, it produces an ‘effect’ on it. In some situations ‘effect’ is also used as a verb while ‘affect’ is applied as a noun.

When ‘affect’ is used as a verb (used with object), it gives the following meanings

To act on; produce an effect or change in
Ex: Rain affected the crops

To impress the mind; move the feeling of
Ex: Her love affected him so deeply

When ‘affect’ is used as a noun

Psychology, feeling or emotion

In psychiatry: observed emotional response that is restricted, flat, or blunted affect, a symptom of mental illness, especially schizophrenia.

Synonyms of ‘affect’: act on, alter, change, disturb, induce, influence,  involve, modify, move, overcome,  relate, transform,  simulate, take on

Effect (Noun)

Something that is produced by a cause; result; consequence
Ex: Exposure to the sunlight had the effect of on your eyes.

Power to produce results; efficacy; force; validity; influence:
Ex: Susan’s stubbornness had no effect on Phill’s mind.

The state of being effective, accomplishment or fulfillment:
EX: put your plan into effect.

Adding special effect

Effect (Verb) –used with objects

Produce as an effect; bring about; accomplish something; make it happen:
Ex: His new ideas about iPhone finally effected the transition.

Synonyms of ‘effect’: aftereffect, aftermath, backlash, backwash,   chain reaction, conclusion, consequence, development, end, end product, event, eventuality, follow-up, issue, outcome, outgrowth, precipitate, pursuance,  reaction, reflex, response, sequel, sequence, side effect

Summary:

As a noun ‘affect’ indicates ‘a feeling or emotion,’ whereas ‘effect’ means ‘the consequence of some action or process’

As a verb, ‘affect’ means ‘to exert an influence upon,’ whereas to ‘effect’ indicates ‘to bring about as a result’

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