"affect" is a verb, and "effect" is a noun.

an E and an A

My easy way to know which to use is that "affect" basically means "change" and "effect" means "result" -- hence the first vowel in each word matches.

Most of the answers given here are correct, so I will not elaborate further. There is another word often misused. I hate it when people say "Light complected" when referring to a person with fair skin. The correct term is "complexioned". There is no such word as "complected". Same goes for "red-headed" in describing a person with auburn hair. It's "red-haired", not "headed". However a red-haired person can be correctly referred to as a "redhead". Correct when used as a noun, but not as an adjective. Go figure! How did I get off the track? Must be the grammarian gremlin in me. Sorry!

dude what grade r u in?? affect is a verb and and effect is a noun!

The word "affect" is a verb. Example usage: "I was affected by the heat, sweating like a pig.". http://dictionary.reference.com/browse/affect The word "effect" is a noun. Example usage: "The effect of the heat was that I sweat like a big." http://dictionary.reference.com/browse/effect

It affects me that you don't know the effect of not knowing this

Both "affect" and "effect" can be nouns, and both can be verbs. Think of the sentence "She was so low in affect that I feared she was clinically depressed." Here, "affect" is a noun meaning external display of internal feelings. "Effect" is the more familiar noun, as in "The effect of summer heat on lawns is severe," but both can be nouns. The distinction between the two when they're used as verbs is the distinction that most people don't see, don't remember, and/or don't bother with. "Affect" is the more common verb, and it means to influence something that is already in existence: "Consumer confidence affects the economy." To "effect" something means to CAUSE it, to bring it about. The something didn't exist till we effected it. "The experimental medication effected a cure." We might have a problem solving discussion and effect a decision.

Something will have an effect on something ie it effects it. A person will affect an accent, if the accent is not real.

Affect or effect? In general use, affect is only used as a verb, whereas effect is commonly used as a noun and only in formal contexts as a verb. What causes confusion is that they have very similar pronunciations and closely related meanings. If one thing affects [acts upon] another, it has an effect on it [causes it to change]. Notice also that you can affect [cause a change in] people as well as things, but you can only effect [bring about] things such as changes: The election has affected our entire society, for it has effected major changes in the government.The bad weather has a bad effect [not affect] on him. http://encarta.msn.com/encnet/features/dictionary/DictionaryResults.aspx?refid=1861583968 affect (noun): feeling associated with action: an emotion or mood associated with an idea or action, or the external expression of such a feeling http://encarta.msn.com/encnet/features/dictionary/DictionaryResults.aspx?refid=1861583970 Affect and effect are frequently confused. Affect is primarily a verb meaning ‘make a difference to’, as in the changes will affect everyone. Effect is used both as a noun meaning ‘a result’ (e.g. the substance has a pain-killing effect) and as a verb meaning ‘bring about (a result)’, as in she effected a cost-cutting exercise. http://www.askoxford.com/concise_oed/affect_1?view=uk affect - (noun -Psychology) emotion or desire as influencing behaviour. — DERIVATIVES affectless adjective. http://www.askoxford.com/concise_oed/affect_3?view=uk affect (1, noun), affect (2, verb), affect (3, transitive verb) http://www.m-w.com/cgi-bin/dictionary?book=Dictionary&va=affect affect (INFLUENCE) - verb [T] to have an influence on someone or something, or to cause them to change. affecting - adjective FORMAL causing a strong emotion, especially sadness. affect (PRETEND) Show phonetics verb [T] 1 FORMAL to pretend to feel or think something: To all his problems she affected indifference. 2 FORMAL MAINLY DISAPPROVING to start to wear or do something in order to make people admire or respect you: At university he affected an upper-class accent. He's recently affected a hat and cane. affected adjective DISAPPROVING artificial and not sincere: an affected manner/style of writing I found her very affected. affectedly adverb DISAPPROVING She laughed affectedly. affectation noun [C or U] DISAPPROVING behaviour or speech that is not sincere: She has so many little affectations. His manner reeks of affectation. "It doesn't concern me, " he said with an affectation of (= pretending) nonchalance. Common Learner Error: affect or effect? Do not confuse the verb affect with the noun effect, which means the result of a particular influence. Global warming is one of the most serious effects of pollution. Do not confuse the verb affect with the verb effect, which is formal and means to make something happen. The management wish to effect a change in company procedure. http://dictionary.cambridge.org/results.asp?dict=B&searchword=affect Noun - (Singular) affect (Plural) affects (psychology) Emotion. (colloquial, psychology) A strong emotional experience. See usage notes below. (psychology) External display of emotion or mood. He seemed completely devoid of affect. Usage notes: The homophones “affect” and “effect” are sometimes confused. “Affect” conveys the influence over something that already exists, but “effect” indicates the manifestation of new or original ideas or entities: “...new governing coalitions during these realigning periods have effected major changes in governmental institutions.” “...new governing coalitions during these realigning periods have affected major changes in governmental institutions.” The former indicates that major changes were made as a result of new governing coalitions, while the latter indicates that before new governing coalitions, major changes were in place, and that the new governing coalitions had some influence over these existing changes. The verbal noun uses of affect are distinguished from the verbal noun uses of effect more clearly than the regular verb forms. An affect is something that acts or acted upon something else. But an effect is the result of an action (by something else.) http://en.wiktionary.org/wiki/Affect http://www.infoplease.com/dictionary/affect http://dictionary.cambridge.org/results.asp?dict=A&searchword=affect The term Affect generally suggests an emotion. It is used in various ways in various contexts: Affect (philosophy). Affect (psychology), referring to feeling or emotion. Affect display (psychology) refers to apparent signs of emotion, such as facial expression, vocalization, and posture Affective science, the scientific study of emotion. Any of several terms in abnormal psychology, including. Blunted affect or affective flattening, a reduction in emotional reactivity. Labile affect, the unstable display of emotion. Affective computing, an area of research in computer science aiming to simulate emotional processes. Literary affects, the emotional experience generated in a reader by a text, such as catharsis, kairosis, and kenosis. Affekt (the German term, which is often used in this context) in musical and other aesthetic theory. (The article currently redirects to Doctrine of the affections.) Doctrine of the affections, an important theory in musical aesthetics. Please note that although the word "affect" is most commonly found in verb form, it also exists as a noun, and as such is often confused with the word "effect" (itself most commonly a noun, but occasionally found in verb form). http://en.wikipedia.org/wiki/Affect http://en.wikipedia.org/wiki/Affect_%28psychology%29 http://en.wikipedia.org/wiki/Affect_%28philosophy%29

I asked this question awhile ago and now back. Hi, there are alot of smart people here and I am amazed that you haven't found the one word answer. Jeff Lovstrom ISA Certified Arborist #7426WE