Cause and Effect

"Affect is a verb; effect is a noun," you say. That's true. You think you're terribly clever for knowing that, don't you? But it is also true that affect is a noun and effect is a verb. Still so clever?

Affect (verb) means to have an impact on, do something to something. Global warming affects the polar ice.
Effect (verb) means to cause something; the most common expression is to "effect change."
Affect (noun) is most commonly a psychological term, meaning someone's outward emotional appearance. When we read that the serial killer seemed like a nice, normal guy, we're discussing his affect. (Pronunciation note: the noun affect gets emphasis on the first syllable.)
Effect (noun) is the result of a cause. The effect of higher global temperatures is polar ice melting. The effect of the serial killer's deceiving affect was that his victims didn't fear him.

Now you are terribly clever. At least regarding these two words.