affect, effect

Affect or affect ( a verb--an action word ) means to produce a change in--
Will the new rules affect our benefits?
Will this medicine affect my vision?
Affect may also mean to produce feelings or emotions in--
Sad movies always affect me this way.
The TV news can affect people in many ways.

Effect or effect ( a noun--a thing or idea) means a result or consequence--
The only effect of the new regulations was more paperwork.
All the lecturing had no effect on him whatsoever.
Effect may mean the main idea or impression--
I don't like the effect that produces.
I'm not sure the effect is what we wanted.

Now that you know that, you can say--
"The effect of the sad movie was to affect everyone for days."
 "This affected me. That had an effect on me."

Note--Affect or affect is a psychological term for emotion--
He was diagnosed with an affective disorder--what they used to call an emotionally disturbed
Note # 2--"effective" means useful for the purpose, or likely to produce a desired result--
This medicine has often been found effective for conditions like yours.
Note # 3--"affected" means to speak or interact socially in a very artificial manner, as in copying speech directly from a movie or novel--
I don't like that woman; she's so affected.
He affects an air of the lord of the manor with his ascot and monocle.
The pose put on in this manner is called an affectation--
That accent is an affectation. She was born in Brooklyn.
Not to be confused with affection, meaning an emotion of fondness or attachment--
Our dog wags his tail in a show of affection.